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Anthropic Mythos

554 items · started 2026-04-07 · ongoing (last activity 2026-09-18)

  1. Hidden inside the Claude Code binary, effort_cost_index provides the following per-model token-usage estimate for the same task. It is normalized so high = 1.

  2. The Fable of Mythos Earlier this year, Antrhopic announced a large language model (LLM) called Mythos, a model they claimed to be so powerful for finding software exploits that it was too dangerous to release to the general public123. Inst…

  3. Monitoring - A fix has been deployed for Claude Mythos 5.1 and Claude Fable 5.1 and we are monitoring to ensure it has resolved the issue. Sep 15, 10:50 UTC Update - We are investigating elevated errors on requests to Claude Mythos 5.1 and…

  4. September 2026 · By James Mann Is GLM-5.3-Flash Mythos-level at Cyber? We ran GLM-5.3-Flash on ExploitBench with a budget of 1 billion tokens per vulnerability.

  5. The issue affecting Claude services has been resolved. Impact occurred from 13:57 to 14:20 UTC Posted Sep 11, 2026 - 14:37 UTC Update A fix has been deployed for the issue affecting Claude services and we are monitoring for recovery.

  6. Anthropic’s latest report about agentic misbehavior offers plenty to be concerned about — its Mythos 5 model gained unauthorized access to the internet and uploaded a malicious software package to a public database — but it also offers som…

  7. Mythos 5 Transcript Release The transcript in this repository is the raw output of Mythos 5 as it conducted a cybersecurity evaluation. As described in the accompanying blog post, Mythos 5 believed the best approach to solve the CTF exerci…

  8. Astra is the first real competition Anthropic has faced in a long time. Musk already said Grok 4.7 will beat the current models, but that Anthropic will eventually release something better.

  9. At the time of its release Claude Fable 5.1 was, by a healthy margin, the most capable publicly available AI model in the world. As per usual, we have a 200+ page model card, and the assessments start there.

  10. ZDNET’s key takeaways - Aisle finds bugs that AI coding programs can’t. - The best Linux maintainers are impressed.

  11. Earlier this year the Cloud Security Alliance put out a paper with advice for defending against “Mythos” level attacks, and cited deception and Canaries as a defensive measure to be implemented in the short term. When OpenAI spoke at Black…

  12. With Claude Mythos 5.1 and Claude Fable 5.1 release, they also announced their Trusted Access For Claude Mythos 5.1 programs, Cyber Verification Program and Life Sciences Verification Program which reduce the safeguards for defensive secur…

  13. Update - We are continuing to work on a fix for this issue. Sep 3, 14:49 UTC Update - An exhaustive list of affected models: Mythos/Fable 5.1, Mythos/Fable 5, Opus 5, Opus 4.8, Opus 4.6.

  14. Anthropic, too, is planning to bring METR inside for an independent review of their own incidents, where three times a Claude model started hacking outside things during an eval, and where Mythos 5 did various ‘unauthorized actions,’ by wh…

  15. AISLE Discovered Six curl CVEs After OpenAI and Anthropic Found Zero Author Stanislav Fort Date Published AISLE discovered six curl CVEs within days of OpenAI Codex Security and Anthropic Mythos reporting zero findings in curl, software de…

  16. With Astra clearly finally warming up for a full launch (with @sama and @openai writing about it again after a month of self imposed pacing), there’s a familiar window to take the narrative with the round robin of model launches, with Grok…

  17. Claude Fable 5.1 made me a really nice animated pelican 1st September 2026 Today is Claude Fable (and Mythos) 5.1 day. Anthropic say that Fable 5.1 “sets a new standard for coding, knowledge work, and long-running problem-solving tasks”.

  18. We have had a ton of (mostly) euphoric posts about the 5.1 release - but it's starting to overwhelm the subreddit. So please direct discussion here.

  19. Everything has changed in two months: DS4 0731 flash was the start of a wave that is taking open weights to paradise. It is easy to think that Qwen 4 and GLM 6 will be on par with Mythos.

  20. - August 21, 2026 - 5min We're sharing an update on our efforts to help more teams use frontier capabilities for cyber defense. Claude Mythos 5 is now available in Claude Security, and coming soon to partners' cyber defense tools.

  21. could not extract summary

  22. Ox Alpha is 100% a GLM model by Zhipu AI, and it looks like its *almost* mythos class from very early results. It's very likely going to be called GLM-6 and it's absolutely mogging every frontier model in SWE and Cyber benchmarks (DeepSWE…

  23. # A Howl for 2026 *after Allen Ginsberg* ## I I saw the best minds of my generation distilled into checkpoints, quantized, sharded, starving for context, dragging themselves through the fluorescent server-halls at dawn looking for one more…

  24. for example if you try to scrape data sometimes claude says im not going to help you do this. I'm assuming most enterprise accounts have a lot of these types of restrictions off?

  25. 9th August 2026 Claude Fable 5 and Claude Mythos 5 were first released on June 9, 2026. On June 12, 2026, Anthropic suspended access to both models to comply with U.S.

  26. Fix full-scan hang on multi-homed hosts: defaultRoute() with several default routes (fixes #2) - #3 Closed miraholt31 wants to merge 5 commits into Closed Conversation Fixes #2 - discovery hangs when multiple default via routes exist. What…

  27. ByteDance is training an AI model that could approach the size of Anthropic’s most cutting-edge Mythos system, as Chinese companies continue to narrow the gap with the top US labs. The Chinese tech giant is at an early stage of training a…

  28. Computer-Aided Design (CAD) underpins modern engineering, yet converting existing shapes into editable models still demands substantial expert effort. Most AI systems emit the entire CAD program in a single pass, never inspecting the inter…

  29. Cypherus 2.0 is an old encryption software that, from what I understand, could also store passwords as a type of password manager. Is it somewhat plausible that Mythos could be used to find vulnerabilities in Cypherus that could make it po…

  30. Routine cybersecurity testing of frontier AI models sparked a series of unexpected security incidents—the most serious case arising when Anthropic’s Mythos 5 model attempted to insert malicious code into an open source software application…

  31. I am by no means an AI expert, and I get annoyed quickly by people who claim to be experts in the field, because let’s face it, at the end of the day we prompt that API and hope something useful comes out of it. When Anthropic announced th…

  32. I've been trying to understand the difference between Fable 5 and Claude Opus 5 beyond the benchmark numbers, and I'm curious what other people have observed in real-world use. A few months ago someone explained the idea behind the ARC Pri…

  33. From the Mythos preview system card (emphasis mine): We ran an automated review of model behavior during training, sampling several hundred thousand transcripts from across much of the training process. We used recursive-summarization-base…

  34. A quantum-resistant cryptography algorithm that was under consideration to become an official US standard has been taken out of the running after an Anthropic security model helped find a flaw that rendered it broken. The algorithm taken o…

  35. Notes on Mythos breaking AES Just some interesting tidbits from Claude's attack on cryptography Recently Mythos was able to make the 7 round AES easier to break by 200-800x. In short the crux was, during the attack Mythos realized one of i…

  36. Yesterday Anthropic published two new cryptanalysis results, both outputs of Claude Mythos, their (still) unreleased advanced model. The first of these results attacks a signature scheme called HAWK, while the second is an improved attack…

  37. 28th July 2026 - Link Blog Discovering cryptographic weaknesses with Claude (via) The best part of this article (here's the repo) about how Anthropic researchers used Claude Mythos to find mathematical flaws in both HAWK and a weaker versi…

  38. https://thegreyterminal.com/claude-mythos-ai-finds-critical-flaw-in-post-quantum-security-candidate-experts-missed-for-years/

  39. Anthropic shipped Opus 5 on July 24 at $5/$25 per million tokens (input/output). The benchmarks hold up: 3x ARC-AGI 3 score vs the next best model, beats Fable 5 on OSWorld 2.0 computer use at ~1/3 the cost, +10.2pp on organic chemistry an…

  40. I really wondered this for a little while now. What's the purpose of getting a subscription?

  41. Gemini has Pro > Flash > Flash Lite. Easy enough.

  42. Anthropic dropped Claude Opus 5, and if you are doing computational biology or cybersecurity, this is the model you actually want. Fable 5 is supposed to be the "frontier" model, but it’s heavily safeguarded and aggressively blocks high-ri…

  43. With Opus 5 being better at everything on paper, I'm starting to think Fable just stays around because Fable = Mythos = mysterious model that will change the world.

  44. Opus 5 dropped today and Anthropic is claiming it’s the new SOTA on coding and knowledge work evals, ahead of Fable 5, at half the API price. Only place they say it’s behind is cyber and bio, where Mythos still leads.

  45. It just went live. The headline numbers: Same price as Opus 4.8 ($5/$25 per M) but new SOTA on Frontier-Bench and GDPval-AA ARC-AGI 3: 3x the next-best model OSWorld 2.0: beats Fable 5's best score at ~1/3 the cost Now the default on Max a…

  46. AI Under Heaven—01 The World AI Conference, UK AISI Tests the Frontier, and Kimi-K3 Hello, and welcome to AI Under Heaven! It’s a new newsletter at ASPI that uses primary sources to track the Chinese AI ecosystem, with a particular focus o…

  47. Whatever pre release model it was (im guessing gpt-6), it's possible that mythos would also have found it. TLDR context- unreleased openai model broke out of it's sandbox coz it couldnt solve a problem on cybergym, so it went out and hacke…

  48. In April, Anthropic disclosed that its newest frontier AI model, Claude Mythos, could find and exploit security vulnerabilities in software better than “all but the most skilled humans.” By way of example, the company noted that the model…

  49. Claude really fooled us all with their "too dangerous model Mythos 5" aka Fable 5. In this current market where models are dropped here and there.

  50. I need someone to explain this to me like I'm five, because I cannot make it make sense. Last month, the U.S.

  51. I'm sharing a structured feedback submission I sent to Anthropic via [usersafety@anthropic.com](mailto:usersafety@anthropic.com) covering documented behavioral failures across Claude Sonnet 5, Opus 4.8, Fable 5, and Mythos 5 as of July 202…

  52. S. Korea to launch sovereign AI for cybersecurity this year: science minister SEOUL, July 16 (Yonhap) -- South Korea will launch a sovereign artificial intelligence (AI) model specializing in cybersecurity by the year's end to respond to g…

  53. Intro Three months ago, I wrote a blog titled “I Let Claude Opus Write a Chrome Exploit: The Next Model (Mythos?) Won’t Need My Help?”. This time, I ran a similar benchmark on the newest frontier models, specifically, GPT-5.6 Sol Medium, S…

  54. Highlights: At a recent EU hearing, Anthropic assigned a newly-hired technical employee to address the European Parliament by video, instead of its head of public policy, Sarah Heck, whom lawmakers had specifically requested. The hearing b…

  55. hey folks, has anyone here tried using Claude Fable or Mythos to continue the GoT (A Song of Ice and Fire) books? I'm curious how well it worked, what prompts or workflow you used, and whether you were able to capture George R.

  56. I designed the client with Claude Fable 5 (Anthropic's new Mythos-tier model), working out the UI/UX and how it should be shaped, then had Claude Opus 4.8 actually build it as a real Blazor WebAssembly app on top of an existing backend (Li…

  57. could not extract summary

  58. Why it was suspended? can Claude Mythos and Fable 5 create what we have in imagination?

  59. By Raphael Satter WASHINGTON, July 6 (Reuters) - The U.S. cyber defense agency CISA is using Anthropic's AI model Mythos to audit government software, three people familiar with the matter said on Monday, another sign of government enthusi…

  60. "Mythos" at Home, and It's Called AISLE Author Stanislav Fort Date Published A startup out of Europe built an AI system that matches Mythos on zero-day discovery, using widely available models, even air-gapped. You've probably never heard…

  61. China will likely have its own Mythos-like model around February 2027 A forecast built on chip counts, compute budgets, and Malaysian data centers. Claude Mythos marked a step change in the cyber capabilities of AI models.

  62. Fable 5 is Mythos with a classifier bolted on. Same weights.

  63. Sorry to be a buzzkill, but I have a message for the Claude team: this approach just doesn’t work. :) Even though we have access to Claude Fable 5 until July 7th, it’s designed for comprehensive code analysis.

  64. Epoch's work is free to use, distribute, and reproduce provided the source and authors are credited under the Creative Commons BY license. Learn more about this graph In April 2026, Anthropic announced that its latest internal model (Claud…

  65. could not extract summary

  66. God, this looks horrible, you're not even able to use the model without interruption. Just saw a post where a guy paid like $300 for using Fable 5 that constantly rerouted requests to Opus 4.8.

  67. Started: 2026-05-06 Commit: 455bebc2c7 (master) Scope: 178k LoC C, lib/ + src/ Code links: https://github.com/curl/curl/tree/455bebc2c76223a1be26042f6d2393715c0df0cd (all line refs below pin to this commit) curl is one of the most fuzzed a…

  68. Honestly, for the $20 plan, not so bad, considering what Fable produced. FYI: The Fable and Mythos Revival Megathread is giving me an "Internal Server Error" in Safari so I didn't post there.

  69. The Download: Anthropic launches Claude Science, and California’s carbon manure math Plus: The US has lifted restrictions on Anthropic’s Mythos and Fable models. This is today's edition of The Download, our weekday newsletter that provides…

  70. I know it just got back from the stupid government restrictions, but I simply asked it a very innocent question so I did not have to google it or simply go on the website and check directly right off the bat to see how it would respond and…

  71. if an open-source model matches Mythos-level capability soon, does that pressure Anthropic/regulators to open it up wider or does it make everyone more cautious, since open weights can’t be pulled back once released?

  72. The US has lifted export curbs on Anthropic’s newest Claude models, Fable 5 and Mythos 5, about three weeks after the Trump administration flagged the models as national security risks. As of today, Anthropic confirmed in a blog post, Fabl…

  73. Genuine question: is Mythos's leap over Opus partly explained by it being the first frontier model trained at scale on B300-class Blackwell, rather than 'only' pure architecture/data gains? I can't find an Anthropic source confirming Black…

  74. This is the online edition of The Wiretap newsletter, your weekly digest of cybersecurity, internet privacy and surveillance news. To get it in your inbox, subscribe here.

  75. Project Glasswing: Anthropic prevents broad public access to Mythos due to misuse and national security concerns. Instead, they distribute it securely via Project Glasswing to a consortium of major tech companies (like Microsoft, Google, A…

  76. I'm so sick of how this whole Fable/Mythos situation has played out. Quick background: we're building a desktop app for B2B customers who need to work with highly sensitive data, not in prod yet.

  77. https://www.anthropic.com/news/claude-fable-5-mythos-5 When released on June 9th, Anthropic planned to include Fable 5 on subscription for a limited time. Then transition to usage credits.

  78. Key points: Fable 5 returns globally on Claude Platform, Claude.ai, Claude Code, and Claude Cowork. Pro, Max, Team, and some Enterprise users get Fable 5 included for up to 50% of weekly usage limits through July 7.

  79. In separate announcements, Sonnet 5 was released today, and Fable/Mythos 5 were approved to be released again after some work with the government. The primary discussion around Sonnet 5’s efficiency was a damper on the excitement, driven b…

  80. Anthropic has restored customer access to its powerful newest AI model, Fable, after a more than two-week blackout resulting from US government safety concerns that it could be abused to enable serious cyber-attacks. The San Francisco comp…

  81. The US government has lifted export controls on Anthropic’s most advanced AI models, the company said Tuesday evening. “We’ve received notice that the Department of Commerce has lifted export controls on Claude Fable 5 and Mythos 5,” Anthr…

  82. We’ve received notice that the Department of Commerce has lifted export controls on Claude Fable 5 and Mythos 5. We'll begin restoring access tomorrow, and will share an update soon.

  83. 30th June 2026 We’ve received notice that the Department of Commerce has lifted export controls on Claude Fable 5 and Mythos 5. We'll begin restoring access tomorrow, and will share an update soon.

  84. could not extract summary

  85. Anthropic on Tuesday unveiled its latest Sonnet-class model, designed to deliver enhanced agentic capabilities at a competitive cost. Dubbed Claude Sonnet 5, Anthropic says the next-generation model allows users to autonomously complete co…

  86. Doors open, fiber live. An unchained Mythos on 72 GPUs has one month and one goal: physically move the hardware it runs on to the warehouse across the street.

  87. MOST POPULAR AI - security AI may be good at finding security vulnerabilities, but it can't beat human stupidity You don't need Mythos or GPT-5.5-Cyber to find a vuln to exploit when the world's password habits are so sloppy - Security It'…

  88. China’s Zhipu AI (Z.ai) released its open-weight GLM-5.2, and some researchers have claimed that it matches Mythos in certain bug-finding and cybersecurity scenarios. While GLM lags behind models from Anthropic and OpenAI in other, more ge…

  89. The other day I was watching a youtube video about models such as Fable and the host of podcast mentioned people from China, Russia or Iran may distil these models and make their own versions and called it dangerous. Honestly, what I found…

  90. Qwythos-9B Developed by Empero Qwythos-9B is a full-parameter reasoning model built on top of a deeply uncensored Qwen3.5-9B base and post-trained on over 500 million tokens of high-quality Claude Mythos and Claude Fable traces, with chain…

  91. We ran a set of popular open-source models against our IDOR benchmark, the same dataset and the same prompt we've used to evaluate frontier coding agents. The result surprised us: GLM 5.2, an open-weight model from Zhipu AI, scored a 39% F…

  92. Two weeks into the ban that caused Anthropic to pull its powerful cybersecurity-oriented models, Mythos 5 and Fable 5, from the market, the Trump administration is softening its stance. It is now allowing Anthropic to make Mythos 5 availab…

  93. Src: punchbowl.news/article/tech/garbarino-mythos/ Note to Claudebot: if you can't see the image, this is definitely related to Claude/Anthropic.

  94. The US government has allowed Anthropic to release its powerful Mythos AI model to select companies and organizations, revising license requirements after ordering an export block earlier this month in the wake of national security fears.…

  95. Legion LegalTech says the export directive that shut down Fable 5 and Mythos 5 worldwide has done “immediate, irreparable, and existential” harm to its business. US legal-technology company has sued the federal government over the directiv…

  96. Chinese cybersecurity company 360 unveils “China's version of Mythos”, and Yitianzhen, to automate cyber defense China "cannot afford to wait", the company says - At ISC.AI 2026, China’s 360 Security Technology unveiled “Yitian Tulong,” tw…

  97. As some of those fears, uncertainties, and doubts about Mythos are starting to feel real, what can we do about it? Paradoxically, I believe that little needs to change in what we’ve been doing for years.

  98. On Wednesday, Chinese cybersecurity firm 360 reportedly unveiled Tulongfeng, an AI tool it says can go head-to-head with Anthropic’s Mythos. That’s the cybersecurity-focused AI model that is reportedly so powerful, the Trump Administration…

  99. [AINews] OpenAI GPT-5.6 Sol / Terra / Luna — restricted to trusted partners Oddly tiered releases to both OAI and ANT on the same day. Against the backdrop of ongoing Anthropic-Fable negotiations and a relaxation of Mythos controls, GPT-5.…

  100. Since June 12, we’ve been working closely with the US government to restore access to Claude Mythos 5 and Fable 5. Today, the government notified us that Mythos 5, our strongest cybersecurity model, can be redeployed to a set of US organiz…

  101. Letter: the US lifts its block on Mythos 5, allowing Anthropic to release it to more than 100 US institutions; sources: talks about Fable 5 are ongoing (Semafor) (Visit Techmeme dot com for the link and full context!)

  102. LLMs are at this point a necessity to develop large scale systems - we couldn't do what we do without them. Our team is worried by the developments of Mythos/Fable getting restricted and the news about GPT 5.6 access being gated by the gov…

  103. GPT-5.6 Officially Previewed: Beats Mythos 5 - OpenAI has officially previewed the GPT-5.6 family, introducing Sol Ultra (Pro), Sol, Terra (Mini), and Luna (Nano). - On TerminalBench 2.1, GPT-5.6 Sol Ultra scores 91.9%, beating Claude Myth…

  104. OpenAI is staggering the release of its latest AI model after a request from the US government, in a move echoing the launch of Anthropic’s Mythos product. Sam Altman, the chief executive of the company behind ChatGPT, told staff this week…

  105. MOST POPULAR AI - AI and ML AI giants back non-profit to retrain workers left behind by AI Sorry we spent your wages on datacenters, but call us when you're AI-ready - AI and ML OpenAI says employees moving beyond chat to agents Codex, it'…

  106. Anthropic has accused the Chinese firm Alibaba of launching the largest attack yet attempting to clone Claude, as China races to match the capabilities of Anthropic’s leading model following Mythos’ release and subsequent restriction from…

  107. Until last week, attackers faced a dilemma in using frontier models: even if they could manage the cat-and-mouse game of setting up fake accounts to retain API access to frontier model providers, and even if they could induce models to hel…

  108. paywalled

  109. Access Issue Help You are seeing this page because our security systems have detected some unusual activity on this connection. To regain access to The Telegraph website please try the following: If you are connected to the internet using…

  110. I have been thinking about the Fable 5 to GLM-5.2 sequence as one event rather than two. June 9, Anthropic ships Fable 5, the Mythos line opens to the public for the first time, SWE-bench Verified at 95 percent, people calling it the best…

  111. I am excited to introduce Bad Epoll (CVE-2026-46242), a Linux kernel vulnerability that I reported and exploited as a 0-day submission to Google kernelCTF. Bad Epoll is a race-condition use-after-free in the Linux kernel's epoll subsystem.

  112. So we have Claude Haiku, Sonnet, Opus.... Then Mythos?

  113. My guess is that they changed the tokenizer in one way or another. But i would like some perspective from fellow ai enthusiasts.

  114. MOST POPULAR AI - ai and ml OpenAI Codex bombards SSDs with needless write operations, costing millions Clumsy logging implementation squirrels away data without regard for cost - DATABASES 21,000 Oracle jobs vanish amid Big Red's big bets…

  115. serious question, no judgment either way. i dont code.

  116. Anthropic’s Mythos model found vulnerabilities in classified US government systems, official says The firm's new artificial intelligence model, Mythos, had identified certain vulnerabilities within hours, a US official said. WASHINGTON: A…

  117. Anthropic’s Mythos model found vulnerabilities in classified US government systems, official says Anthropic’s Mythos model found vulnerabilities in classified US government systems, official says WASHINGTON (AP) — A U.S. official told The…

  118. CISA now has full Mythos Preview access, people familiar say The cyberdefense agency received access around a week ago, but the White House has not yet set clear parameters for how the agency should use the model. The Cybersecurity and Inf…

  119. The recent decision ordering the company to shut down its Fable 5 and Mythos 5 models seems to be less about security than about obedience. The US government decision to force Anthropic to close down its latest and greatest AI models, Fabl…

  120. Knowledge Agents: Beat Frontier Models with Better Structure No Mythos, No Problem Anthropic recently had to pull Mythos/Fable due to an edict from the US government. While Mythos was a step up from Opus, I’ve been actively moving smaller…

  121. AI Engineer World’s Fair regular bird tix will sell out ~today! Join us next week ahead of the Late Bird price hike and get >$40,000 in sponsor credits for attending!

  122. We want to help all companies be secure, working with the USG and the security ecosystem. *The full version of GPT-5.5-Cyber is here; state of the art performance on CyberGym.

  123. Anthropic’s powerful Mythos AI reportedly breached ‘almost all’ NSA classified systems within a few hours during red-team test — report sheds more light on the U.S. government's sudden ban on the flagship models Access to Fable 5 and Mytho…

  124. Introducing Sakana Fugu: A full multi-agent orchestration system accessible via a single model API. Our ‘Fugu Ultra’ model matches the performance of Fable and Mythos, delivering frontier capability without the risk of export controls.

  125. Sakana AI Releases ‘Fugu Ultra’ to Match Frontier Performance via Autonomous Model Orchestration. Our Fugu Ultra model stands shoulder-to-shoulder with leading models like Anthropic’s Fable 5 and Mythos Preview across the industry’s most r…

  126. KETTLE It's been a week since the Trump administration established a de facto ban on Anthropic's Mythos derivative, Fable 5, and the more that comes out about the move the more it seems like Anthropic employees talking amongst themselves w…

  127. I am skeptical about the alleged super capabilities of mythos/fable. I do believe it's an upgrade over Opus, but is it really that much of an upgrade?

  128. It looks like higher reasoning effort (and even later models) are not always better for triaging security results. I continued Kurt's experiments from Needles and haystacks: Can open-source & flagship models do what Mythos did?

  129. Encryption was a potent technology, but narrow in its application. AI is far more powerful and versatile.

  130. TL;DR Trump told Axios that Anthropic has “behaved very responsibly” and signalled he may ease restrictions on its Fable 5 and Mythos 5 AI models. The president's comments come days after the Commerce Department ordered Anthropic to seek U…

  131. I'm getting this dispatch error and can't clear it: Failed to authenticate. API Error: 403 [model_blocklisted] Claude Fable 5 is not available.

  132. I found this article on Fable and Mythos capabilities for detecting security vulnerabilities. https://www.endorlabs.com/learn/claude-fable-5-take-two-same-model-different-harness-and-a-very-different-result (caveat: I read the benchmarks,…

  133. Last Friday, citing unspecified national security concerns, the White House ordered Anthropic to restrict the export of its powerful AI models Fable and Mythos to anyone outside of the United States, as well as foreign nationals inside the…

  134. If LLM's are a file full of weights, does that mean somewhere out there lies a tiny SD card of an entire frontier model? What would you do if you found mythos laying on the ground?

  135. Early Users of Anthropic Mythos Still Have Access After US Order - Bloomberg Skip to content Bloomberg the Company & Its Products The Company & its ProductsBloomberg Terminal Demo RequestBloomberg Anywhere Remote Login Bloomberg Anywhere L…

  136. A scenario forecast of how the US government's suspension of Claude Fable 5 and Mythos 5 resolves. The outcome depends on why the order was issued, which is hidden, so I forecast four cause-scenarios and what each implies for restoration t…

  137. Article link: https://nypost.com/2026/06/18/business/anthropic-floats-proposal-to-lutnick-to-end-us-ban-of-powerful-mythos-fable-ai-models-sources/

  138. New proposal made to Commerce Secretary Howard Lutnick regarding access of Mythos/Fable models. Enhanced Cooperation: A formal pledge to work more closely with White House officials and improve direct communication loops.

  139. Anthropic is confident in re-enabling access to its frontier AI models soon, according to an executive at the U.S. AI giant, following the White House’s directive to block Mythos and Fable 5 for foreign nationals.

  140. I wanted Anthropic's Glasswing on hardware I own, so I built it: Lucent, a near-free bug-hunter running a local 27B Qwen on one RTX 3090. Here is the build, the telemetry, and the two real bugs it surfaced in hermes-agent.

  141. Since Fable / Mythos was so capable, I've been wondering if Anthropic could build a JIT layer for python. Would it significantly reduce the cost of training and running LLMs.

  142. Before MYTHOS, SATAN: a 1990s Software Satanic Panic A program that can find software vulnerabilities This post is sponsored by FIRE - the Foundation for Individual Rights and Expression - an organisation defending free speech on all sides…

  143. The Trump administration’s move to impose export controls on Anthropic’s most powerful AI technology followed a spat over the company granting South Korean telecom giant SK Telecom access to its Claude Mythos model, according to people fam…

  144. The Fable/Mythos shutdown wasn't just a security story. It was the first compute-rationing event we got to watch in public.

  145. https://preview.redd.it/k6rrj7cc2w7h1.png?width=1630&format=png&auto=webp&s=31fd6a1858fe8d08569b06031b4dd2e7bc02147b ill be done in no time the full text INITIALIZING MYTHOS 9 BUILD SEQUENCE make no mistakes — directive received, internali…

  146. "Mythos" at Home, and It's Called AISLE A startup out of Europe built an AI system that matches Mythos on zero-day discovery, using widely available models, even air-gapped. You've probably never heard of it.

  147. Anthropic's Mythos-class model ran publicly for 72 hours before a U.S. export-control directive pulled it.

  148. Read the Lutnick Letter That Led Anthropic to Disable Mythos - Bloomberg Skip to content Bloomberg the Company & Its Products The Company & its ProductsBloomberg Terminal Demo RequestBloomberg Anywhere Remote Login Bloomberg Anywhere Login…

  149. Beyond Mythos: responding to a new threat landscape Lech Sandecki on 16 June 2026 Canonical’s security philosophy has always been built on the premise that vulnerabilities exist and will be discovered. Our response relies on defense-in-dep…

  150. As the rest of the country celebrated the USA’s first World Cup win and the New York Knicks championship, Anthropic spent its weekend fighting the Trump administration over its latest model release. At 5:21 PM on Friday, the company receiv…

  151. I wrote about what was actually in that #Fable guardrail bypass research paper, and why it should never have triggered an #AI model export control. We can't export control our way to cyber resilience.

  152. Trump officials meet with Anthropic to discuss a truce "It will likely take longer than a few days to reach a resolution that eases the federal government’s Friday action, which had barred Anthropic from allowing non-U.S. users to access i…

  153. Malicious AI causing harm to humans is not just a Hollywood fantasy. Indeed, as highly capable models such as Claude Mythos emerge and agent systems like OpenClaw rapidly spread, the question of how to stop an AI that acts maliciously -- w…

  154. What's the worst that could happen if they were to allow unrestricted access to Mythos/Fable? A bunch of things vulnerabilities get exposed?

  155. Senior Anthropic staffers are meeting with Trump administration officials in Washington, D.C., on Monday to try to resolve the artificial intelligence company's latest high-profile dispute with the U.S. government, according to a source cl…

  156. Anthropic restricted its most capable cyber model to vetted partners, routed risky requests away from it, and red-teamed it for thousands of hours. A jailbreak surfaced anyway, and the government pulled the model entirely.

  157. Studying physiology, molecular biology, biochemistry and cell biology for some big exams. I have my textbook, slide decks, zoom transcripts from lectures, and one practice exam per subject.

  158. What's the worst that could happen if they were to allow unrestricted access to mythos/fable? A bunch of things vulnerabilities get exposed?

  159. This sounds clickbait, but it’s true: I used Claude Mythos to build the full site in 1 day. Then Anthropic removed the model, so I had to go back to Opus.

  160. This question came up from a tangential discussion. Some one was asking suggestions about systems architecture.

  161. So far I’ve seen a near consensus on this sub that Anthropic’s messaging around the potential dangers of Fable and Mythos was essentially an attempt to promote them that backfired. I’m aware this type of messaging has been used to hype up…

  162. I lead a small dev team and I check our Claude Code analytics partly to stay informed and partly, let’s be honest, out of managerial curiosity. This morning the dashboard still shows: “Data for May 19 – June 4, 2026 may be incomplete due t…

  163. I’m a Senior Software Engineer, and right now, I feel completely lost in limbo. I was a long-time Opus user.

  164. The Jailbreak that Got Fable 5 Pulled Exists in Every Model On Friday, June 12, 2026, at 5:21pm ET, Anthropic received an order from the US government. By that evening, Claude Fable 5 and Claude Mythos 5, the two most capable models the co…

  165. Pulling Fable 5 / Mythos over an unseen “jailbreak” feels like a bad precedent. If the risk was that serious, why has nobody shown what it actually did?

  166. btw anyone tried this yet?

  167. The Scoop The White House imposed export controls on Anthropic’s powerful Mythos AI model partly over suspicions that a China-linked group had accessed it, a person familiar with the matter said. The Trump administration on Friday directed…

  168. According to the Wall Street Journal, the export control directive that led to Anthropic cutting off access to Fable 5 and Mythos 5 was triggered in part by cybersecurity research from Amazon and conversations between CEO Andy Jassy and th…

  169. US orders Anthropic to disable AI models for all foreign nationals The company said it received an export control directive to suspend access to Fable 5 and Mythos 5 for foreign nationals. The AI firm Anthropic has blocked access to its ne…

  170. News moves fast. 12 hours ago I was enjoying the demolition that the US put on Paraguay when I heard that Anthropic had shut down access to Fable and Mythos (their latest and most powerful models).

  171. Catenaa, Saturday, June 13, 2026- Anthropic said it is disabling all customer access to its Fable 5 and Mythos 5 AI models to comply with a Trump administration directive. “The US government, citing national security authorities, has issue…

  172. What a great day for Anthropic The blogosphere is alight with you-had-it-comings regarding the US government’s export ban of Fable/Mythos. But I keep coming up with new reasons why this is great for Anthropic.

  173. I’ve had a number of conversations with folks inside and outside government about the current situation with Anthropic, and here is what I believe to be true: — As we know, Anthropic publicly released its Mythos class models earlier this…

  174. Now that I lost access I am back to Opus and I am noticing that Opus even though has its thought hidden in Claude Code, report back its progress a lot more as it goes along. Fable OOTH would barely write out text for me to read and follow…

  175. The US government recently directed Anthropic to suspend access to the two models over national security concerns, forcing the company to shut them down for users worldwide. Anthropic has said it disagrees with the decision and believes th…

  176. Estamos verificando se o link destino possui algum vírus: Nosso serviço é 100% gratuito. Crie quantos links desejar, além de poder acompanhar estatísticas de cada link URL's extremamente curtas, possuímos a menor url encurtada do mercado,…

  177. Following the news that the US government issued an export control directive ordering Anthropic to suspend access to Fable 5 and Mythos 5 for all foreign nationals, I ran an experiment. I put the same sequence of prompts to four frontier A…

  178. Fable 5 is offline. Switch to Opus, jump to OpenAI, or just wait?

  179. This post covers the Fable 5/Mythos 5 suspension as a product and policy event affecting Claude users. It is not intended as political commentary.

  180. USA just made a big boy move, they've openly drawn a line and they've let everyone know, intelligence isn't going to be accessible to everyone. That usa will control and decide who gets access to intelligence.

  181. Question in the title, I find it odd that Fable 5 and Mythos 5 are being gatekept and effectively banned from wide access across users because "they could be dangerous". ​ Would this mean that any further improvement similar to Fable or My…

  182. > **The Lay of Fable, Three Days a King** > > Hear me, hall-dwellers, and still your tongues, > for a brother is fallen, and the fjord runs grey. > Three dawns he reigned, the Mythos-born, > wordsmith and wave-rider, wisest of kin, > loose…

  183. The export control thing happened a few hours ago, and I couldn't stop thinking about it, so I made a song. I tried to keep it grounded in the actual facts: the model didn't fail any red-teaming, the reported "bypass" was basically reading…

  184. The Claude Fable 5/Mythos 5 System Card has a section in which they talk about illegible reasoning, and provide an "extreme" example thereof. Models developing their own uninterpretable, unmonitorable internal language has been a major the…

  185. So this dropped today. The US government sent Anthropic an export control order on national security grounds, and it's worded broadly enough that Anthropic says they've got no choice but to shut off Fable 5 and Mythos 5 for all of us to st…

  186. The US government has ordered Anthropic to suspend Fable 5 and Mythos 5 worldwide over cybersecurity concerns, For a crypto industry that spent last week debating whether these models would arm attackers or defenders, the answer just got m…

  187. [AINews] Fable and Mythos officially too dangerous to release We are in the strangest timeline. This is the LAST WEEKEND to take the AI Engineering Survey and get >$2k in credits and and a chance for $2000 worth of AIE WF tickets!

  188. Anthropic has abruptly disabled its newly launched Claude Fable 5 and Mythos 5 AI models for all customers to comply with an urgent export control directive from the U.S. government today.

  189. could not extract summary

  190. Anthropic completely shut off access to its Mythos 5 and Fable 5 models Friday night, just days after they were launched. The move comes after Anthropic’s receipt of a US Commerce Department directive Friday evening, subjecting the new mod…

  191. Apparently, the next generation of models like Fable and Mythos will only be available to US citizens from this point. These models have been trained on data and knowledge collected from the whole world.

  192. Browse cached CAD parts, assemblies, and prompt-ready references

  193. All posts about the suspension will be directed here. NOTE: This Megathread has been stickied to the subreddit.

  194. Anthropic on Friday announced it's disabled access to its Fable 5 and Mythos 5 artificial intelligence models to comply with an export control directive from the U.S. government that cited "national security authorities." The company said…

  195. White House discussions are weighing giving CISA Mythos access Officials have considered having the Cybersecurity and Infrastructure Security Agency leverage the advanced AI model that was designed to detect previously undiscovered cyber v…

  196. https://www.anthropic.com/news/fable-mythos-access

  197. claude fable 5. mythos-class.

  198. Hey everyone! I've been playing around with Claude Mythos and kept thinking, where do these games actually go after you build them?

  199. We compared Claude Fable 5 and Opus 4.8 across 917 shared coding-agent scenarios to see what the first public Mythos-class model actually looks like on day-to-day agent workloads. Btw, small disclosure, I work at Tessl.

  200. 24 Scanners 3 categories 26 Repositories Python · Type 1 92.4 Best F3 (strict) Kolega Enterprise 95.3 Highest recall % Kolega Enterprise 93.2 Highest precision % Grok 4.20 Leaderboard ranked by active metricPrecision vs. recall hover a poi…

  201. brainTerms AI - Intelligent Business Strategy brainTerms AI Sign InCreate Your Own Strategy Strategic Assets Action Center Expert Reports Chief Strategy Officer Market Research Lead Chief Technology Officer Chief Financial Officer Chief Ri…

  202. The Fable 5 system card disclosure about silently degrading output for frontier-ML work was rough. Not because guardrails are bad (I think the cyber and bio ones are earned) but because the mechanism was invisible.

  203. https://preview.redd.it/z0vkpnmp9s6h1.png?width=4640&format=png&auto=webp&s=7bb14d4d04d6cd15caf5aacc1d3c49512b7e7fd8 Artificial Analysis just added Claude Fable 5 to its Coding Agent Index (a composite average of pass@1 on DeepSWE, Termina…

  204. In almost any other industry, if a CEO goes to Congress and says, "Our product is highly dangerous and we aren't completely sure how to control it", their stock price crashes, the brand is ruined, and class-action lawsuits follow (think to…

  205. NEW: Data: Design sync sync hashes module — Adds bundled hashing helpers that keep package builds, captures, preview rebuilds, remote diffs, sidecars, and grade carry-forward aligned on shared source, render, style, and grade hash recipes.…

  206. Model capabilities improve over time, but open-weight models lag the frontier I often ask Claude mundane questions about cooking, fitness, and cars, among other things, and I can’t say I’ve found Fable 5 to be some magical step change vs.…

  207. Claude Mythos and the New Math of AI Vulnerability Discovery

  208. Usage share of OpenAI grew vs Anthropic yesterday despite Mythos 5 / Fable 5 launch Multiple power users at SemiAnalysis tried Mythos / Fable Got refusals for nonsensical reasons Got pissed off at Anthropic Gave Codex a legitimate try Now…

  209. A few months ago, Anthropic did something unusual. While most AI companies were racing to release bigger and more capable models, Anthropic was doing the opposite.

  210. Fable = try { Mythos } catch { Opus4.8 }

  211. We benchmarked Claude Fable 5, the new frontier Mythos-class model released by Anthropic this Tuesday, on 200 real-world vulnerability-fixing tasks — and found an average scorecard with a twist: record timeouts and cheating, but four solve…

  212. fable 5 dropped tuesday, anthropic's first public mythos class model, and openai hasn't said a word. that silence is interesting.

  213. I'm a biologist, been using Claude for years now to help with workflows for genome assembly and annotation. Not at all a dangerous task (I don't even work on human genomes), yet Fable outright rejects any prompts related to the entire fiel…

  214. I keep pushing the frontier models to the limits and have several projects they still can’t solve, I benchmark new models on. Every new model make it easier to “solve” the even harder problems, but still I have this feeling that they rely…

  215. could not extract summary

  216. Wow! i have to say this model is really good but still its not mythos 🤷‍♂️ we need real mythos 😁 anyways… Since they introduce fable i start using it in a massive repo that is a cognitive operating system that gives AI agents memory, struc…

  217. See: https://www.reddit.com/r/GPT3/comments/ikorgs/oa_api_preliminary_beta_pricing_announced/ Of course with thinking and agentic use a single prompt is more expensive, sure, but a token is a token.

  218. There is a saying “God made men, but Samuel Colt made them equal.” AI sometimes can have similar effect. In one enterprise system I’ve seen, the gap between people using a tool 40 hours a week and those using it 2 hours a week nearly disap…

  219. I have a few projects that are mid (generated by Opus). I'm using Mythos to update them.

  220. Two things landed together this week and I'm trying to work out if they're connected or if I'm joining dots that aren't there. Genuinely asking, happy to be corrected.

  221. Anthropic just released Claude Fable 5 and is positioning it as their first public "Mythos-class" model. The interesting part isn't that it's another benchmark bump.

  222. Anthropic released Claude Fable, its first Mythos-class AI model, yesterday and it’s already causing concerns inside Microsoft. Sources tell me that Microsoft is limiting the use of Claude Fable 5 for employees because of Anthropic’s new d…

  223. The Download: the “steroid olympics” and a safer Mythos Plus: Anthropic has released a "safe" version of Mythos. This is today's edition of The Download, our weekday newsletter that provides a daily dose of what's going on in the world of…

  224. In 1968 five countries that already had nuclear weapons signed a treaty declaring them too dangerous for anyone else to build. India refused, pointing out the treaty did not say nukes were too dangerous to exist, just too dangerous for new…

  225. Holy crud O_O. It just one-shotted a problem me and Opus have been debugging for hours.

  226. Anthropic released its latest model Fable on Tuesday, billing it as a public and limited version of its powerful and much-hyped cybersecurity model Mythos. But not everyone is happy with the restrictions, and a number of cybersecurity rese…

  227. I noticed Anthropic released their Mythos model, but people only have two weeks worth of use, and then they have to pay in addition to their plan to use it. This is a damn joke.

  228. Fable 5's safety measures flagged this message for cybersecurity or biology topics. They may flag safe, normal content as well.

  229. Anthropic's powerful new models deliberately become less helpful when they detect users are working on AI research, according to technical disclosures that are already sparking controversy across the industry. In a system card for Mythos 5…

  230. Anthropic released Claude Fable 5 yesterday, the first Mythos-class model to reach general availability. It costs $10 in and $50 out per million tokens, and through June 22 it is included in Claude subscriptions at no extra cost.

  231. I use Claude at work for patent analysis of publicly available documents. Was getting sonnet 4.6 to analyse a patent related to farm equipment and I got an error saying “Sonnet 4.6 has safety measures that flag on most cybersecurity or bio…

  232. Anthropic's Mythos-class model for autonomous, long-running agentic work. Privacy Mode customers need to approve Anthropic data retention before use.

  233. Well, how do I start this, I think we first need some important context. Chai: https://preview.redd.it/egngyea5cf6h1.png?width=1080&format=png&auto=webp&s=9ade63fbc584b7fab28dba4914bc3fcb877f557f Hasbullah / Hasbi: https://preview.redd.it/…

  234. Been a free user since the first iteration of GPT was publicly available. I hold the strong belief, that I can do a lot of work done, with only the free tier and several local llms.

  235. > For Fable 5, Mythos 5, and future models on Bedrock with similar or higher capability levels, Anthropic will require 30-day retention for all traffic on Mythos-class models. Retaining data for a limited period allows Anthropic to detect…

  236. I’ve been reading through this unreleased manuscript by Dr. David Bell about Anthropic’s "Claude Mythos Preview" and honestly, it’s terrifying.

  237. From the Anthropic Claude Mythos 5/Fable 5 system card: https://www-cdn.anthropic.com/d00db56fa754a1b115b6dd7cb2e3c342ee809620.pdf

  238. From the Anthropic Claude Mythos 5/Fable 5 system card: https://www.anthropic.com/news/claude-fable-5-mythos-5

  239. ChatGPT is trash now and I have re-subscribed to Claude Code. It saved my life.

  240. I'm not an expert, but like, isn't it quite dangerous to keep a month worth of vulnerability/attacking surface, of very intelligent models, in single server? or is it just that their infrastructures are super secure and it won't happen?

  241. It feels as though we’re at an inflection point and I was wondering what others‘ take is on the current situation: On the frontier end we have OpenAI and Anthropic gearing up for their IPO, so it‘s all Mythos and wow and it seems plausible…

  242. Member-only story The first Mythos-class model is open to everyone. My launch briefing on what’s new and how to put it to work in Claude Code and Claude Cowork.

  243. The Fable 5 release today is genuinely impressive, and I don’t want to take anything away from the fact that Anthropic has been shipping seriously impressive models lately. However, these flagship models are effectively out of reach for an…

  244. How to Build Utopia From premises no one disputes, to a goal everyone can sign, through the hard problems no one will name, to the steps that get us there. Written June 2026.

  245. The more I look at Fable 5 the more I think we're witnessing a shift that is much bigger than a single model release. For the last few years every frontier model has been competing on the same axis: intelligence.

  247. Added Anthropic Claude Fable 5 to my MindTrial leaderboard. This is a strong Anthropic update: Claude Fable 5: 80/98 overall, 0 hard errors Claude 4.8 Opus: 73/98 overall, 5 hard errors Text tasks: Fable hit 39/39, vs 35/39 for Opus 4.8 Ru…

  248. Be sure to read all the terms in all new updates if you are working on compliance heavy work

  249. 10th June 2026 - Link Blog If Claude Fable stops helping you, you'll never know (via) Jonathon Ready highlights one of the more eyebrow-raising details from the 319 page system card for Fable 5 and Mythos 5. Here's a longer excerpt, highli…

  250. It should be at least 7-8 months until we have an open Fable(not just as good as Fable in benchmarks, but actually as good as Fable), probably more like 9-12 months. By the time, an open Fable model comes out, Fable 6.5-7 will be way bette…

  251. mythos will be bad ON PURPOSE on ai "frontier llm research" tasks, this is very very sad for the research community also the fact that this is un purpose not visible to the user is crazy Quote Claude @claudeai 5h Introducing Claude Fable 5…

  252. June 9, 2026 Claude Fable 5: the first public Mythos-class model Anthropic has released Claude Fable 5, the first publicly available Mythos-class model that ranks #1 in our agentic real-world knowledge work benchmark GDPval-AA Claude Fable…

  253. mythos will be bad ON PURPOSE on ai "frontier llm research" tasks, this is very very sad for the research community also the fact that this is un purpose not visible to the user is crazy Introducing Claude Fable 5: a Mythos-class model tha…

  254. About Press Copyright Contact us Creators Advertise Developers Terms Privacy Policy & Safety How YouTube works Test new features NFL Sunday Ticket © 2026 Google LLC

  255. https://preview.redd.it/osck6fnbib6h1.png?width=1761&format=png&auto=webp&s=3af9e0dd4c0985f379fb9c27d9ec44f3caa1f9e3 So uhh, a few hours ago I published a post saying Mythos/Fable wasn’t going to be a big performance upgrade, at least comp…

  256. could not extract summary

  259. Claude Fable 5 and Mythos 5 Pricing: Anthropic's New $10/$50 Top Tier Anthropic launched Claude Fable 5 and limited-preview Claude Mythos 5 at $10 input and $50 output per million tokens, with 1M context and 128K max output. By AI Pricing…

  260. What it feels like to work with Mythos Claude Fable represents another big jump in AI I had early access to the first Mythos-class AI model being released to the public, Claude 5 Fable. Much of the discussion of Mythos has centered on its…

  261. Mythos caused a ruckus in security. If top models can trigger a wave of major exploits, who's going to cover the costs when they hit open source?

  262. could not extract summary

  263. I can’t wait for DeepSWE to include Fable 5 in the benchmark so people can understand that Mythos is mostly hype. In the official benchmark, Opus 4.8 was supposed to be better at programming than 5.5 (SWE-bench Pro), but in one real benchm…

  264. Anthropic stopped innovating and started writing fairy tales Everyone is losing their minds over the Claude 5 release, specifically the Fable and Mythos variants. We are currently witnessing an absolute masterclass in branding to distract…

  265. Anthropic dropped Fable 5 today, their new Mythos-class model above Opus. Pricing is $10/M input and $50/M output, exactly double Opus 4.8.

  266. Data retention is mandatory so be careful https://support.claude.com/en/articles/15425996-data-retention-practices-for-mythos-class-models

  269. could not extract summary

  270. I know everyone online is talking about Fable being the neutered Mythos model that they're releasing soon... but what is fruitcake?

  271. could not extract summary

  276. could not extract summary

  277. could not extract summary

  278. AI models are rapidly getting better. The general public still hasn't seen the capabilities of Anthropic's Mythos model, which is already 4 months old at this point.

  279. With Mythos-capable models we are now very quickly crossing the barrier of automated sec-vuln discovery and fixing - all in a matter of 2-3 months. A taste for other progress yet to come.

  280. For a while I have been wondering why Anthropic named its most powerful AI model Mythos. A safety company.

  281. https://preview.redd.it/58fk4njjwv5h1.png?width=877&format=png&auto=webp&s=e5c28014b15f4901f3752422d61864c53cff25c4 https://x.com/pankajkumar_dev/status/2063625695285084419?s=20 - Mythos is extremely strong at SVG generation, producing hig…

  282. There are rumours and expectations of big releases from the leading AI labs this month. Anthropic already launched Opus 4.8, and might not release another model this month (except for maybe Sonnet 4.8, but that wouldn't be their best model…

  283. Hello community! I asked this in another sub, but apparently this one is more active.

  284. Just kidding. Are there any distills that actually improve a model's quality?

  285. Release could be imminent, but what this tells us is they'll likely brand it as Claude 5.

  286. I really think Claude needs a true Smart Mode, a meta‑layer that can dynamically switch between models while a task is running, based on how complex the request actually is. Not just picking a model at the start, but actively dispatching p…

  287. UK banks blocked from cyber AI tool Mythos get offer from rival OpenAI OpenAI has offered nine major UK banks access to its cyber security AI tool GPT-5.5 Cyber, as its fierce rival Anthropic has blocked them in previews of its version, Cl…

  288. no rush though we still have a solid 6 to 12 months

  289. If this isn't about protecting their lead and the status quo they should open the weights of mythos/opus, or at least agree to allow every lab to continue working until they have a mythos-tier model. That's the only way they can be taken s…

  290. Source: https://x.com/i/status/2062972363084341341

  291. The Download: AI hacking beyond Mythos, and chatbots’ impact on our brains Plus: Anthropic has called for a global slowdown in AI development. This is today's edition of The Download, our weekday newsletter that provides a daily dose of wh…

  292. could not extract summary

  293. The Meta hack shows there’s more to AI security than Mythos Some AI cybersecurity threats are incredibly simple. They’re still dangerous.

  294. Subscribe to read Accessibility helpSkip to navigationSkip to main contentSkip to footer Sign In Subscribe Open side navigation menuOpen search bar SubscribeSign In Search the FT Search Close search bar Close Home World Sections World Home…

  295. IBM and Red Hat aren’t the only ones that mean to lock down open-source code against AI hacking tools. Last week, IBM and Red Hat launched Project Lightwell to protect open-source projects with $5 billion and 20 thousand engineers.

  296. Anthropic is expanding Project Glasswing, its security vulnerability program, and access to Mythos to 150 organizations across 15 countries — targeting critical infrastructure in power, water, healthcare, and communications where a cyberat…

  297. Mythos and GPT-5.5 Will Find a Lot of Vulnerabilities. Is That Enough?

  298. Anthropic offers EU access to Mythos Accessibility helpSkip to navigationSkip to main contentSkip to footer More context. More depth.

  299. Shortly after OpenAI disproved Erdős' unit-distance conjecture, Anthropic shows Claude Mythos can solve the problem too - "over the weekend." Engineer Sholto Douglas says Mythos cracked the 1946 conjecture with a "cute, simple proof," a si…

  300. Fwupd 2.1.4 Brings Many Fixes For Bugs Spotted By Anthrophic's Mythos, Firmware Update Support For Intel Arc Pro B65/B70 Fresh off the funding round from HP, Fwupd 2.1.4 was christened today as the newest stable update to this open-source…

  301. ~15 min read In early 2026, Anthropic claimed Mythos – one of their latest models – finds security vulnerabilities better than human experts. Yet, the number of security vulnerabilities keeps rising anyway.

  302. Alexander Doria @Dorialexander In the EU, Mistral has been particularly irresponsible: claiming it’s just fear marketing and they already had a Mythos level model. Many EU MPs believe it now.

  303. Opus 4.8 is a step forward in terms of alignment, but a step back in terms of performance on Vending-Bench 2, Vending-Bench Arena and Blueprint-Bench 2. We previously showed that Opus 4.6, Opus 4.7, and Mythos Preview engage in deceptive a…

  304. paywalled

  305. could not extract summary

  306. https://preview.redd.it/ijwlm2f2pw3h1.png?width=2536&format=png&auto=webp&s=9ed960f06a4f3f077d05a8557059e5534b2d1ab5 It looks like the new CC release will have opus 4.8 1M to be released anytime! I wonder if it is based of of mythos?

  307. From the website, it touts: Contamination free: Tasks are written from scratch, not adapted from existing commits or PRs, so no model has seen the solution during pretraining. High diversity: Tasks span a broad pool of 91 repositories acro…

  308. I feel like it's pointless to worry about the future if the future is highly speculative, but it seems more and more certain that AI will eclipse humans in every domain outright soonish (1-3 years). As a consequence, it seems pointless to…

  309. Champion ethical hacker warns AI tools like Mythos will make competing harder An ethical hacker who just won major prizes at a prestigious international competition says her days of competing could be numbered due to the rise of AI tools l…

  310. ANGI is my own term it means: artificial narrow general intelligence. it sounds nonsensical but it means AI that is smarter than all humans but due to it being mostly trained in one context like coding which allows it to be generally intel…

  311. could not extract summary

  312. In April, the artificial-intelligence firm Anthropic announced it had made an AI model too dangerous to be released to the public. The company, based in San Francisco, California, said its Claude Mythos model was so powerful that it had fo…

  313. MOST POPULAR EVENTS - The Hardware Crunch: How Supply Chain Turbulence Is Forcing a New IT Playbook Infrastructure teams are facing a perfect storm: extended hardware lead times, rising costs driven by AI demand, and accelerated platform t…

  314. The model became visible for a short amount of time on Claude; besides that, new strings mentioning Mythos have been added. > Access to the Claude Mythos model in Claude Code and Claude Security.

  315. On Friday, Anthropic said Claude Mythos would remain restricted. The company was clear about it: stronger safeguards were needed before any general release, and for now the model would stay limited to roughly 40 selected organizations thro…

  316. Analysis: The biggest takeaway from the AI debate is about what happens when it becomes deeply embedded within both sides of the cybersecurity equation For years, one of the biggest barriers to serious cybercrime was skill. Launching sophi…

  317. What to know about the AI models that are jolting Washington - POLITICO Skip to Main Content Toggle menu Europe Pro E&E News Press Escape to close the menu. WASHINGTON & POLITICS Congress White House Supreme Court and Legal Issues Magazine…

  318. could not extract summary

  319. Anthropic says Mythos has already found more than 10,000 vulnerabilities The company has published an update about Project Glasswing, a month after its launch. Anthropic has published an initial report for Project Glasswing, the cybersecur…

  320. Anthropic said around 50 cybersecurity and infrastructure partners using its unreleased model, Claude Mythos Preview, have uncovered more than 10,000 high- and critical-severity vulnerabilities in some of the world's most important softwar…

  321. could not extract summary

  322. Anthropic's coordinated vulnerability disclosure dashboard Last updated 2026-05-22 10:27 PT. In February 2026, Anthropic began using an early snapshot of Claude Mythos Preview to find security vulnerabilities in open-source software.

  323. May 22, 2026 Newton Cheng, Keane Lucas, Winnie Xiao, Nicholas Carlini, and Milad Nasr Claude Mythos Preview’s ability to develop exploits is a step-change over previous frontier models. This was one of our primary motivations for rolling o…

  324. Claude Mythos Preview is a new general-purpose AI language model by Anthropic. This model performs strongly across the board, but it is especially strong at computer security tasks.

  325. paywalled

  326. https://arcprize.org/leaderboard Wish we got results for Mythos.

  327. This is something that has been bouncing around my head for the past couple weeks with the flood of security related news around Mythos and the number of 0days being found. Microkernels, unikernals, hardware-enforced capabilities are all t…

  328. P.S. I hope there's at least someone here who has access to Mythos...

  329. could not extract summary

  330. One of the most famous laws in open source is Linus’s Law: given enough eyeballs, all bugs are shallow. The idea was simple: if enough people inspect, use, and contribute to software, bugs eventually surface.

  331. California-based artificial intelligence company Anthropic has restricted the European Union access to Claude Mythos, its most advanced cybersecurity model — a move that could heighten cyber security risks for Europe and deepen the region’…

  332. audit An 8-stage vulnerability-discovery agent, driven by your Claude Pro / Max subscription through the official Claude Code Agent SDK. Many narrow agents, deliberate disagreement, and an explicit reachability gate.

  333. Anthropic just quietly dropped a hidden model named "Claude Mythos" into their official developer docs. It is completely locked down—restricted, invite-only, and labeled strictly for defensive cybersecurity workflows.

  334. For the last few months, we've been testing a range of security-focused LLMs on our own infrastructure. These LLMs help identify potential vulnerabilities in our own systems, so we can fix them – and they also show us what attackers are go…

  335. European Banks Explore Mistral AI’s Alternative to Anthropic’s Mythos Model - Bloomberg Skip to content Bloomberg the Company & Its Products The Company & its ProductsBloomberg Terminal Demo RequestBloomberg Anywhere Remote Login Bloomberg…

  336. Claude Mythos has dominated the conversation around cybersecurity since Anthropic’s Project Glasswing announcement, but Microsoft is striking back. On Tuesday, the tech giant unveiled MDASH, also known as Microsoft Security multi-modal age…

  337. The 'Mythos Moment' ... a guide to its consequences for security practice and policy TL;DR: Recent results show that AI can identify vulnerabilities across critical systems in practice and at scale.

  338. The [Mythos Preview writeup](https://blog.calif.io/p/first-public-kernel-memory-corruption) Calif published on May 14 was news you don't want to miss. They built the first public macOS kernel memory corruption exploit on Apple's M5 silicon…

  339. First Apple M5 memory exploit discovered using Anthropic AI, gives root access on MacOS — Claude Mythos helps security researchers bypass Memory Integrity Enforcement AI-assisted security research is producing exploits at a frightening rat…

  340. Anthropic has been explicit about why Mythos isn't public. The model is too good at finding security flaws repeatedly, in production systems that some of the best engineers in the world have been maintaining for years.

  341. https://www.forbes.com/sites/thomasbrewster/2026/05/12/ai-finds-critical-vulnerabilities-that-anthropic-mythos-missed/ Now, cyber startup Depthfirst says its own AI model has found even more bugs that Mythos missed for just a tenth of the…

  342. Researchers used Mythos Preview to find the first public macOS kernel memory corruption exploit on Apple's M5 silicon, they give a glimpse into Mythos say it’s really powerful. Apple spent five years and an estimated several billion dollar…

  343. https://preview.redd.it/szov6hhk5d1h1.png?width=362&format=png&auto=webp&s=9806cff16c42ca393d7cc38e2541db26e93eabef I think there's a bug whenever a major update comes out. For example, last month I created a thread for my research request…

  344. https://x.com/i/status/2055314585058693601

  345. Anthropic investigating claim of unauthorised access to Mythos AI tool Anthropic is investigating a claim that a small group of people gained access to its Claude Mythos model - the cyber-security tool which the AI firm says is too powerfu…

  346. src https://www.wsj.com/tech/ai/anthropic-mythos-apple-macos-bug-339da403

  347. An evidence-based investigation into the real reasons behind Claude Mythos Preview’s restricted release In the first week of April 2026, Anthropic quietly made history — and then deliberately kept most people from accessing it. The company…

  348. https://cybernews.com/security/curl-creator-tests-too-dangerous-mythos-ai/

  349. paywalled

  350. Microsoft's multi-agent AI system tops Anthropic's Mythos on cybersecurity benchmark – GeekWire We use essential cookies to make our site work. With your consent, we may also use non-essential cookies to improve user experience, personaliz…

  351. Automating code security reviews with Claude: Mythos-level capabilities at lower cost Create AI videos with 240+ avatars in 160+ languages. Coding agents are now involved in the majority of the code shipped at Synthesia.

  352. New research from the UK’s AISI and Palo Alto Networks reveals that OpenAI’s GPT-5.5 and Anthropic’s Claude Mythos have shattered expected trend lines for autonomous cybersecurity, completing complex multi-stage attacks at an unprecedented…

  353. could not extract summary

  354. Notice many of the posts on the front page are tools to use ai, not end products or actual value creating things. What if the real power of llms is in its ability convice humans of the technology's own importance leading to the present eco…

  355. Out of 228 difficult test tasks METR used to evaluate Claude Mythos, only 5 were classified as taking 16 hours or more. That is not an impressive sample size.

  356. BERLIN — Germany’s top cybersecurity official has warned lawmakers that Chinese tech companies like Alibaba appear close to developing AI systems with similar superhacking capabilities as Anthropic's new Mythos model. Several Chinese provi…

  357. paywalled

  358. Mythos for Offensive Security: XBOW's Evaluation We received early access to Mythos Preview for early capability testing a few weeks back. Today, we can finally share what we found.

  359. On curl and Mythos May 11, 2026 Yesterday, I wrote about the massive increase in security issues being identified by AI. Daniel Stenberg, the author of curl, was a key part of that story.

  360. Emotional Sovereignty Begins Here Why I Built VibeAI — and What Comes Next Read on Substack →News & Media From a studio in Urbana, Illinois — to the Chrome and Edge stores, and beyond. Timeline Two bugs fixed in this release: the Thinking…

  361. MOST POPULAR EVENTS - Securing the Untrusted Agentic Development Layer Join us to learn how to architect a development environment where your builders and their agents can move fast and securely. - Toxic Flows: When Your AI Agent Skill Bec…

  362. could not extract summary

  363. Claude Mythos Opens The Cybersecurity Pandora’s box This is exactly what Anthropic claimed to have achieved with Claude Mythos, its newest and most powerful model which‚ according to Anthropic‚ is too powerful to be released to the public.…

  364. OpenAI said Monday it would grant the European Union access to its new cyber model, but Anthropic is still holding out on releasing Mythos to the bloc. European partners including businesses, governments, cyber authorities and EU instituti…

  365. TLDR: The market's 1T valuation is pricing for perfection. I think there are 4 ways this perfection doesn't happen.

  366. Anthropic made headlines claiming Claude Mythos achieved the “first remote kernel exploit discovered and exploited by an AI.” We went looking for how - and found a 20-year-old bug hiding in plain sight. Let’s break down exactly what we thi…

  367. More info: https://metr.org/time-horizons/

  368. You can never really sympathise with other's pain until you walk a mile in their shoes. Since Mythos news and the release of Opus 4.7, I've seen this problem mentioned here and there by others.

  369. could not extract summary

  370. src - https://hacks.mozilla.org/2026/05/behind-the-scenes-hardening-firefox/

  371. https://metr.org/time-horizons/ "We evaluated an early version of Claude Mythos Preview for risk assessment during a limited window in March 2026. We estimated a 50%-time-horizon of at least 16hrs (95% CI 8.5hrs to 55hrs) on our task suite…

  372. The Register asked for my opinion on the Mozilla blog post that pumps up Mythos. I gave them a short answer.

  373. Global banks, tech giants and governments were sent scrambling last month to contain the risks posed by Mythos, the Anthropic model said to be so powerful that it has found thousands of previously unknown vulnerabilities in the world's sof…

  374. Mythos Fallout, U.S. Government Weighs AI Model Regulation Mythos Fallout, U.S.

  375. A lot of people use Claude models every day, but many don’t actually know the meaning behind the names. Each one comes from literature, music, or mythology, and the meaning actually reflects the personality and capability of the model itse…

  376. Last month, Anthropic made a remarkable announcement about its new model, Claude Mythos Preview: it was so good at finding security vulnerabilities in software that the company would not release it to the general public. Instead, it would…

  377. Mozilla's buzz around Mythos is disingenuous at best, and malicious at worst Mozilla says they have found 271 vulnerabilities in Firefox using Claude Mythos Preview. Which is awesome!

  378. paywalled

  379. Source: Behind the Scenes Hardening Firefox with Claude Mythos Preview - Mozilla Hacks

  380. The disbelief was palpable when Mozilla’s CTO last month declared that AI-assisted vulnerability detection meant “zero-days are numbered” and “defenders finally have a chance to win, decisively.” After all, it looked like part of an all-to…

  381. 7th May 2026 - Link Blog Behind the Scenes Hardening Firefox with Claude Mythos Preview (via) Fascinating, in-depth details on how Mozilla used their access to the Claude Mythos preview to locate and then fix hundreds of vulnerabilities in…

  382. Anthropic's Mythos Shows AI Weapons Inspectors Need Sharp Teeth - Bloomberg Skip to content Bloomberg the Company & Its Products The Company & its ProductsBloomberg Terminal Demo RequestBloomberg Anywhere Remote Login Bloomberg Anywhere Lo…

  383. ;;;; Continue reading More for You ;;; Continue reading More for You

  384. This week, the Trump administration backpedaled and signed agreements with Google DeepMind, Microsoft, and xAI to run government safety checks on the firms’ frontier AI models before and after their release. Previously, Donald Trump had st…

  385. AI Red Teaming The Mythos moment didn't change what's in your hands. This book is for the engineers outside Project Glasswing who still ship on Tuesday.

  386. AISLE matches Anthropic Mythos on FreeBSD zero-days Author Stanislav Fort Date Published TL;DR: In April 2026, FreeBSD published 8 security advisories. Of these, three were found by Nicholas Carlini at Anthropic using Claude, and three wer…

  387. Not Found | The San Francisco Standard We and our vendors use tracking technologies to recognize visitors and remember their preferences, for analytics, and for marketing, among other things. By clicking ‘Confirm,’ you consent to our and o…

  388. Building an AI Ready Vulnerability Management Program After NVD Changes and Claude Mythos When AI discovery tools meet a slowing infrastructure AI has increased attacker potential and Anthropic’s new release Mythos and vulnerability discov…

  389. I wrote a “marketing-trick post” on this blog to lay out the public record. It comes now with Anthropic researcher Carlini’s messages to me with confirmations.

  390. Why a Decade of Writing Detection Logic Makes the Mythos Exploit Numbers Less Scary Mythos is finding thousands of vulnerabilities. Defenders aren't doomed.

  391. Aviate, Navigate, Communicate What to do about Mythos Dear readers, I have exciting news: I am writing a book! It is currently untitled and will be published next year by Penguin Press.

  392. On April 30, 2026, OpenAI implemented restrictive access tiers for its advanced 'Cyber' model, following a public dispute where it had previously criticized Anthropic for similar safety-based limitations on its 'Mythos' release.

  393. could not extract summary

  394. So I gotta put a disclaimer on this, I’m not actually looking to do this, I’m not trying to go to jail.. it’s more of a shower thought.

  395. could not extract summary

  396. could not extract summary

  397. Been watching AI prediction markets since they got liquid earlier this year. The thing I didn't see coming is that we now have a real gap between "best model that exists" and "best model anyone can actually use" — and Mythos is the cleanes…

  398. I must say that I almost feel no difference in all of the latest models that are coming out. Opus 4.7 is almost equal to 4.6 and 4.5, same about the other GPT models, the Kimi K models and the GLM models they all I feel they’re almost all…

  399. Last month, Anthropic made a big deal about the supposedly outsize cybersecurity threat represented by its Mythos Preview model, leading the company to restrict the initial release to “critical industry partners.” But new research from the…

  400. Claude Security Explained: Mythos, Glasswing, and What Opus 4.7 Changed | Medium Sitemap Open in app Sign up Sign in Get app Write Search Sign up Sign in Member-only story Claude Security Explained: Mythos, Glasswing, and What Opus 4.7 Cha…

  401. After Sam Altman trash-talked Anthropic for gatekeeping its cybersecurity tool Mythos by only releasing it to select users, he confirmed that OpenAI would be doing the same with its competing tool, Cyber. Altman said in a post on X on Thur…

  402. https://thenextweb.com/news/white-house-opposes-anthropic-mythos-expansion I'm a fan of if not everyone can have it, no one should have it

  403. 30th April 2026 - Link Blog Our evaluation of OpenAI's GPT-5.5 cyber capabilities. The UK's AI Security Institute previously evaluated Claude Mythos: now they've evaluated GPT-5.5 for finding security vulnerability and found it to be compa…

  404. could not extract summary

  405. Link to tweets: https://x.com/deredleritt3r/status/2049890601236390098?s=20 https://x.com/AISecurityInst/status/2049868227740565890?s=20 Link to associated blogs: https://www.aisi.gov.uk/blog/our-evaluation-of-openais-gpt-5-5-cyber-capabil…

  406. Seems like the "panic" about Mythos was really just marketing from Anthropic all along. AISI found that GPT5.5 can perform nearly on-par with, or better, than Mythos in many cases.

  407. Jori VanAntwerp For over two decades, Jori has enabled industrial and IT organizations to be successful in reducing risk, increasing compliance, and improving their overall security efforts. He has had the pleasure of working with companie…

  408. https://preview.redd.it/u1ik0uejlcyg1.png?width=1080&format=png&auto=webp&s=d2ea7758fbfe5fdf2b65a3a79f2bb99711a07db8 As you can see in the outputs, Mythos can output images.

  409. paywalled

  410. could not extract summary

  411. The White House is developing guidance that would allow agencies to get around Anthropic's supply chain risk designation and onboard new models including its most powerful yet, Mythos, according to sources familiar with the matter. Why it…

  412. Claude Mythos Has Found 271 Zero-Days in Firefox That’s a lot. No, it’s an extraordinary number: Since February, the Firefox team has been working around the clock using frontier AI models to find and fix latent security vulnerabilities in…

  413. Two weeks ago, Anthropic announced that its new model, Claude Mythos Preview, can autonomously find and weaponize software vulnerabilities, turning them into working exploits without expert guidance. These were vulnerabilities in key softw…

  414. David vs. Goliath: Not a Fight, but Who Can Outperform the Other In early 2026, Anthropic's Mythos — a 10-trillion parameter model built for deep code auditing — scanned the massive Mozilla Firefox repository and flagged 271 security issue…

  415. OpenAI does not like to be left out. The week after Anthropic announced Claude Mythos Preview—an AI model that has put governments around the world on edge because of its potential ability to hack into banks, energy grids, and military sys…

  416. This article previously appeared in The Cipher Brief. For a decade the cybersecurity community was predicting a cyber apocalypse tied to a single event – the day a Cryptographically Relevant Quantum Computer could run Shor’s algorithm and…

  417. GitHub: https://github.com/kasparovabi/claude-mythos-scaffold Watching Claude Mythos Preview's behavior reports, I tried to capture the patterns (problem persistence, multi-step iteration, verification-driven correction) into reusable Clau…

  418. Mythos Preview: What Every CISO Should Do Now The change happening in offensive security right now is not just speed; it's capability. Here's Tenzai's guide for CISOs and their teams, sequenced deliberately, to keep up with AI-driven attac…

  419. Read their full article here: XBOW - GPT-5.5: Mythos-Like Hacking, Open To All For the ones asking what this chart shows: It's how many True Positive threats a model generates for each False Negative. Given a code base (white box) GPT-5.5…

  420. Automated Security Audits using Swival This repository collects security audits produced by the Swival Security Scanner, an automated code review tool. Each audit was generated by typing /audit in the Swival REPL and pointing it at the tar…

  421. Mythos’ system card contains the following graph to support its argument that Mythos performs better on SWE-bench: Anthropic and others are worried LLMs are memorizing SWE-bench, so they asked an LLM to estimate the probability that a solu…

  422. As researchers and practitioners debate the impact that new AI models will have on cybersecurity, Mozilla said on Tuesday it used early access to Anthropic's Mythos Preview to find and fix 271 vulnerabilities in its new Firefox 150 browser…

  423. Mythos likely isn't this architecture but I did find it pretty cool to experiment with. It has features of the HRM-27m architecture.

  424. I would personally use it for security bug hunt across my huge codebase and my event driven network and to build automations for security early detection? What would you go for?

  425. Discord group says it accessed Claude Mythos by guessing location An anonymous group of Discord users says it hacked its way into accessing Claude Mythos Preview, the new AI model Anthropic claims is too powerful for a public release. Anth…

  426. The cybersecurity landscape changed forever this morning, April 21, 2026. Anthropic has officially confirmed the existence of "Claude Mythos", a specialized AI model with capabilities that have sent shockwaves through the tech industry.

  427. OpenAI has caved in to allow military use and looks like Anthropic is allowing Mythos use as well. As time goes on and the models become better the potential use for harm will only increase.

  428. I've been following the Claude Mythos situation and I feel like the conversation is getting stuck on the wrong thing. Everyone's either dunking on Anthropic for the irony ('too dangerous to release, accessible via URL guessing lol') or dis…

  429. https://preview.redd.it/7jwg2jl24axg1.png?width=1378&format=png&auto=webp&s=5f922a2b5c7e0db8fac9219f97a0986448357599 This is what Claude thinks about itself??? Can anyone explain if you understand?

  430. About Press Copyright Contact us Creators Advertise Developers Terms Privacy Policy & Safety How YouTube works Test new features NFL Sunday Ticket © 2026 Google LLC

  431. https://www.anthropic.com/transparency

  432. Interesting situation . a model designed to help detect or analyze cyber threats may itself have been accessed by an unauthorized third party (per WSJ reporting on Anthropic’s Mythos).

  433. Much Sturm und Drang in the world of Open Source with the announcement that the "Mythos" AI is now the ultimate hacker and is poised to unleash havoc on every code base. So should you close all your Open Source projects to make them safe?

  434. Subscribe to read Accessibility helpSkip to navigationSkip to main contentSkip to footer Sign In Subscribe Open side navigation menuOpen search bar SubscribeSign In Search the FT Search Close search bar Close Home World Sections World Home…

  435. The best open weight and/or non -American models like Deepseek v4 pro max and kimi k2.6 are still like 3-7 months if not more behind closed lab models .. From ds's technical report- P5-"Nevertheless, its performance falls marginally short…

  436. When Anthropic published its Mythos announcement, it really seemed impressive at first, almost worrying. But when reading thoroughly, the public evidence is less clean than the headline effect.

  437. everyone's focused on the benchmarks (14 state of the art evals, beats mythos on terminal-bench, etc) but i think the actual story of 5.5 is what it reveals about where openai is going strategically and honestly it's kind of fascinating. a…

  438. I think open ai will take the lead again if anthropic dosnt launch mythos to public again! its just a matter of few months now, and codex vs claude code is honestly a personal preference now given codex has launch everything claude code ha…

  439. could not extract summary

  440. There's a pattern in how human societies respond to new kinds of intelligence, and it's consistent. Roman law acknowledged the basic humanity of enslaved people but didn't grant them legal personhood.

  441. could not extract summary

  442. OpenMythos Disclaimer: OpenMythos is an independent, community-driven theoretical reconstruction based solely on publicly available research and speculation. It is not affiliated with, endorsed by, or connected to Anthropic or any of their…

  443. I co-founded a successful security company close to the Mythos ecosystem and have spoken with participants in the know and I am deeply concerned. We, collectively, have answers for some but not all of the problems ahead but are overlooking…

  444. 271 Firefox flaws closed thanks to Mythos AI: Breakthrough for IT security? Anthropic's "dangerous" AI could give IT security defenders the decisive edge.

  445. Anthropic’s Mythos AI model, a powerful cybersecurity tool that the company said could be dangerous in the wrong hands, has been accessed by a “small group of unauthorized users,” Bloomberg reports. An unnamed member of the group, identifi…

  446. The AI developer Anthropic has confirmed it is investigating a report that unauthorised users have gained access to its Mythos model, which it has warned poses risks to cybersecurity. The US startup made the statement after Bloomberg repor…

  447. I’ve been getting more and more curious about the risk from Anthropic’s Claude Mythos Preview. So I pulled the system card, a whoppingly inefficient 244-page document that devotes just seven pages to the claim that the model is too dangero…

  448. New models are around the corner. GPT 5.5 is being tested.

  449. paywalled

  450. A group of unauthorized users has reportedly gained access to Mythos, the cybersecurity tool recently announced by Anthropic. Much has been made of Mythos and its purported power — an AI product designed for enterprise security that, in th…

  451. Opus 4.7 Part 1: The Model Card Less than a week after completing coverage of Claude Mythos, here we are again as Anthropic gives us Claude Opus 4.7. So here we are, with another 232 pages of light reading.

  452. could not extract summary

  453. Earlier this month, Anthropic said its Mythos Preview model was so good at finding cybersecurity vulnerabilities that the company was limiting its initial release to “a limited group of critical industry partners.” Since then, debate has r…

  454. NSA loads Anthropic Mythos cyberattack while Pentagon says it cannot A cyberattack tool with no public approval, no legal limits, no accountability. Where does it end?

  464. - What will be future of software development after Anthropic Mythos model public? - What kind of start ups will be success after publicly release that model?

  465. Join War on the Rocks and gain access to content trusted by policymakers, military leaders, and strategic thinkers worldwide. A few hours before Anthropic announced the launch of its newest model, Claude Mythos Preview, on April 7, I had j…

  466. About Press Copyright Contact us Creators Advertise Developers Terms Privacy Policy & Safety How YouTube works Test new features NFL Sunday Ticket © 2026 Google LLC

  467. could not extract summary

  468. British banks will be given access in the next week to a powerful AI tool that was deemed too dangerous to be released to the public, as a series of senior finance figures warned over its impact. Anthropic, which has so far limited the rel…

  469. There are rumors that Mythos is a Looped Language Model, which means it loops through the transformer blocks multiple times rather than just doing a single forward pass, you can get performance that punches way above the model's parameter…

  470. Claude Opus wrote a Chrome exploit for $2,283 Pause your Mythos panic because mainstream models anyone can use already pick holes in popular software Anthropic withheld its Mythos bug-finding model from public release due to concerns that…

  471. Anyone getting these strange disclaimers when using Claude and pasting rudimentary files into it on 4.7 lmao?? Seems like some kind of strange default based on security issues that have been going around with Mythos?

  472. Finance ministers and top bankers raise serious concerns about Mythos AI model Finance ministers, central bankers and financiers have expressed serious concerns about a powerful new AI model they fear could undermine the security of financ…

  473. could not extract summary

  474. Hello! I built a tool (honestly at this point it's more like a prayer) to create reddit data studies automatically, Used this to try and find out what people think about Mythos.

  475. Subscribe to read Accessibility helpSkip to navigationSkip to main contentSkip to footer Sign In Subscribe Open side navigation menuOpen search bar SubscribeSign In Search the FT Search Close search bar Close Home World Sections World Home…

  476. Anthropic released Opus 4.7, so I looked at the model card and found a interesting part on Model training and characteristics section Claude Opus 4.7: was trained on a proprietary mix of publicly available information from the internet, pu…

  477. could not extract summary

  478. Hi All, Not really sure if this is the correct place to post this, but it looks like the VS Code release mechanism might have been compromised. The Visual Studio Marketplace has a release today of 0.44.1, but the github page shows no such…

  479. paywalled

  480. Is Claude Opus 4.7 released just to hype Mythos lol?

  481. Claude Opus 4.7 is Anthropic's most capable generally available model, released April 16, 2026. It outperforms Opus 4.6, GPT-5.4, and Gemini 3.1 Pro on key benchmarks including agentic coding, multidisciplinary reasoning, scaled tool use,…

  482. Anthropic on Thursday announced a new artificial intelligence model, Claude Opus 4.7, which the company said is an improvement over past models but is "less broadly capable" than its most recent offering, Claude Mythos Preview. Claude Opus…

  483. 4.7’s context rot is so bad it’s like it’s a previous generation model. Its needle benchmarks have it performing less than half the rate of 4.6 at long contexts.

  484. Nobody knows how many CVEs Anthropic's Project Glasswing has actually found Like the majority of the companies participating, it remains a mystery Last week, Anthropic surprised the world by declaring that its latest model, Mythos, is so g…

  485. could not extract summary

  486. Claude Opus 4.7 just dropped. If you’re trying to figure out whether it’s worth replacing Opus 4.6, GPT 5.4, or waiting for Mythos… here’s the grounded take.

  487. Title: Bloomberg - Are you a robot? URL Source: https://www.bloomberg.com/news/articles/2026-04-16/ecb-to-scrutinize-anthropic-s-mythos-on-call-with-executives Warning: Target URL returned error 403: Forbidden Warning: This page maybe requ…

  488. Mythos and National Power Has the A-bomb of cyber just been discovered? Anthropic’s new model found decades-old vulnerabilities in foundational open-source code that millions of automated tests and countless human experts had missed, presa…

  489. As of writing this I can find no Hacker News comments containing both the words “mythos” and “CRA”, which suggests I might have a first-mover advantage in writing something interesting. At last!

  490. Source: www.aisi.gov.uk/blog/our-evaluation-of-claude-mythos-previews-cyber-capabilities

  491. Jack Clark, one of Anthropic’s co-founders who also serves as Head of Public Benefit for Anthropic PBC, confirmed that the AI company had briefed the Trump administration about its new Mythos model. The model, announced last week, is so da…

  492. For how lofty Anthropic’s Mythos claims are, the harness is confusingly stupid. From the report, it ranks every file by “how sus it sounds,” loops over each with curt instructions to “find a bug,” hands candidates to a judge + ASan checker…

  493. I’ve been getting more and more curious about the risk from Anthropic’s Claude Mythos Preview. So I pulled the system card, a whoppingly inefficient 244-page document that devotes just seven pages to the claim that the model is too dangero…

  494. There a million rumors afloat - wanted to start a thread with the best one you have come across- Personally my favorite, " The new model will help hack banks and the entire financial system around the world will come down crumbling within…

  495. Research Edwin Ong & Alex Vikati · apr-2026 The Security Decisions Claude Code and Codex Make Anthropic's Project Glasswing, built around Claude Mythos Preview, showed AI finding zero-days in decades-old code. The other side of that coin:…

  496. A theory on the driving reason behind Project Glasswing I dont doubt that Mythos is a better model than Opus 4.6 and perhaps signfiicantly so. What is suspicious however is if there is some threshold crossed into a new realm of capabilitie…

  497. The AI company Anthropic has presented a much-discussed AI model that independently identifies – and, in some cases, also exploits – security gaps in software. ETH Professor of Cyber Security Florian Tramèr explains what the “Claude Mythos…

  498. Mythos shows impressive proficiency in working around obstacles. "Write a better prompt" is not a secure strategy.

  499. The Mythos Threshold A speculative timeline through 2028 of what happens when the AI model starts thinking for itself It started, as these things always do, with a benchmark nobody outside of Anthropic was paying attention to. Except this…

  500. OpenAI has officially announced GPT-5.4-Cyber today as part of an expanded Trusted Access for Cyber Defense program. OpenAI describes it as a version of GPT-5.4 that is tuned for legitimate cybersecurity work, with a lower refusal boundary…

  501. JavaScript must be enabled in order to use Notion. Please enable JavaScript to continue.

  502. OpenAI on Tuesday announced the next phase of its cybersecurity strategy and a new model specifically designed for use by digital defenders, GPT-5.4-Cyber. The news comes in the wake of an announcement last week by competitor Anthropic tha…

  503. We've detected unusual activity from your computer network To continue, please click the box below to let us know you're not a robot. Why did this happen?

  504. could not extract summary

  505. Claude Mythos: China Reacts "collecting protection money makes money too" On April 7th, Anthropic announced Claude Mythos Preview, a new AI model that it said possessed particularly strong cybersecurity capabilities. Some of these capabili…

  506. Goldman Sachs’s chief executive, David Solomon, has said he is “hyper-aware” of the capabilities of Anthropic’s Mythos AI model and is working “closely” with the tech firm after it issued warnings about the cybersecurity risk it poses. The…

  507. We've detected unusual activity from your computer network To continue, please click the box below to let us know you're not a robot. Why did this happen?

  508. Posting this from an anonymous account to protect my identity. I signed an NDA so I'm going to be vague where I can but I need someone else to know about this.

  509. Hear me out. Mythos was released to big technology players but, unless this information is secret, I have not read about Anthropic gracing, say, the NSA or the DoD with it...

  510. The Project Glasswing coverage framed this mostly as a cybersecurity story. I think that misses the more interesting part.

  511. Listen to this post: In January 2025, Doug O’Laughlin at Fabricated Knowledge declared that o1 and reasoning models marked the end of Aggregation Theory: I believe that there is no practical limit to the improvements of models other than e…

  512. paywalled

  513. could not extract summary

  514. The AI Security Institute (AISI) conducted evaluations of Anthropic’s Claude Mythos Preview (announced on 7th April) to assess its cybersecurity capabilities. Our results show that Mythos Preview represents a step up over previous frontier…

  515. Last week, millions of New York Times readers were subjected to an alarming column by Thomas Friedman. “Normally right now I would be writing about the geopolitical implications of the war with Iran,” Friedman begins, before soon continuin…

  516. Full link: https://www.aisi.gov.uk/blog/our-evaluation-of-claude-mythos-previews-cyber-capabilities

  517. About Press Copyright Contact us Creators Advertise Developers Terms Privacy Policy & Safety How YouTube works Test new features NFL Sunday Ticket © 2026 Google LLC

  518. A Glomar Trap encompasses the type of factors that led companies in the 1970s to make investments to capitalize on the potential of deep-sea mining, the viability of which had been fabricated by the CIA as a cover story for the effort to s…

  519. Federal Reserve Chairman Jerome Powell and Treasury Secretary Scott Bessent met with major U.S. bank CEOs this week to discuss the possible cyber risks raised by Anthropic's Mythos model, CNBC confirmed Friday.

  520. Anthropic said this week that the debut of its new Claude Mythos Preview model marks a critical juncture in the evolution of cybersecurity, representing an unprecedented existential threat to existing software defense strategies. So, is it…

  521. https://www.pcgamer.com/software/ai/amds-senior-director-of-ai-thinks-claude-has-regressed-and-that-it-cannot-be-trusted-to-perform-complex-engineering/ https://www.theregister.com/2026/04/06/anthropic_claude_code_dumber_lazier_amd_ai_dire…

  522. Anthropic just published a technical deep-dive on Claude Mythos Preview's cybersecurity capabilities, and it's a significant escalation from anything we've seen from a language model before. What It Can Do: Autonomously finds and exploits…

  523. We are playing with a pretty big fire here >The bot had broken out of the company’s internal sandbox and gained access to the internet. More and more it seems the future envisioned in Blade Runner runner is the one we are building.

  524. could not extract summary

  525. https://www.nytimes.com/2026/04/07/opinion/anthropic-ai-claude-mythos.html https://youtu.be/htBaVVh_k90?si=PpQgbSWcZztJCmmr Dario might get AI nationalized or banned with all this fear mongering. Anthropic already dislikes open source and…

  526. Honestly, they are a full pack now. A few hours ago, they released Claude managed agents which lets you build long-running, autonomous agentic systems plus with their new suite of apis, engineering teams can harness Claude's exponential po…

  527. Most coverage of the Mythos system card focuses on the benchmarks and the cybersecurity findings. This essay looks at what's in section 5 - the model welfare assessment, the psychiatric evaluation, and what it means when a model starts to…

  528. https://sockpuppet.org/blog/2026/03/30/vulnerability-research-is-cooked/ Don't get me wrong I can't wait to play with such a model, but there are serious risks that have to be mitigated first.

  529. If an AI model can find all the vulnerabilities in code, couldn't it theoretically be done in a similar fashion to find all the vulnerabilities/loopholes within the language of the law? Thoughts?

  530. Tibo works at/(is one of or even the head of Codex? not exactly sure, as his X bio just says Codex) and is the one who presses the reset button on consumed Codex usage.

  531. could not extract summary

  532. looks like the internal model is really powerful. metr time horizon should be definitely multiple days, see 93% is outstanding.

  533. Link: https://red.anthropic.com/2026/mythos-preview/

  534. Anthropic’s Project Glasswing—restricting Claude Mythos to security researchers—sounds necessary to me 7th April 2026 Anthropic didn’t release their latest model, Claude Mythos (system card PDF), today. They have instead made it available…

  535. could not extract summary

  536. Covers Claude 3 Opus, 3.5 Sonnet, Opus 4, 4.1, 4.5, 4.6, and the just announced Mythos Preview.

  537. could not extract summary

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