Anthropic's Mythos AI faces unauthorized access as security breach exposes controlled rollout flaws
37 Sources
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Unauthorized group has gained access to Anthropic's exclusive cyber tool Mythos, report claims
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 the wrong hands, could become a potent hacking tool,
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Do you need to worry about Mythos, Anthropic's computer-hacking AI?
A powerful AI kept from public access because of its ability to hack computers with impunity is making headlines around the world. But what is Mythos, does it really represent a risk and might it even be used to improve cybersecurity? The past few weeks have brought apparently alarming news of
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Anthropic's Mythos breach was humiliating
Anthropic's tightly controlled rollout of Claude Mythos has taken an awkward turn. After spending weeks insisting the AI model is so capable at cybersecurity that it is too dangerous to release publicly, it appears the model fell into the wrong hands anyway. According to Bloomberg, a "small group
[4]
Anthropic's New Mythos Model Reportedly Accessed By Unauthorized Users
In early April, Anthropic announced its latest Mythos model, saying it would remain exclusive to select tech companies for cybersecurity purposes. Anthropic has now confirmed it's actively investigating an incident where a group claims to have unauthorized access to Mythos. A Bloomberg report,
[5]
Anthropic Mythos shaping up as nothingburger
And that unauthorized access? 'A nothing burger,' hacking startup CEO tells El Reg Anthropic's Mythos model is purportedly so good at finding vulnerabilities that the Claude-maker is afraid to make it available to the general public for fear that criminals will take advantage. But early analysis
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Why Anthropic's Mythos Is Sparking Global Alarm
Anthropic PBC has said its new artificial intelligence tool, Mythos, is too powerful to release to the general public. The AI giant has described the model as so good at finding vulnerabilities in software and computer systems that it will only be released to a limited number of carefully chosen
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Anthropic's Mythos model accessed by unauthorized users, Bloomberg News reports
April 21 (Reuters) - A small group of unauthorized users has accessed Anthropic's new Mythos AI model, Bloomberg News reported on Tuesday, citing documentation and a person familiar with the matter. A handful of users in a private online forum gained access to Mythos on the same day that
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Anthropic investigating unauthorised access of powerful Mythos AI model
Anthropic is investigating whether a group of users gained unauthorised access to its Claude Mythos model, which was only released to a handful of trusted companies because of its advanced cyber security capabilities. The AI lab on Tuesday said it was looking into reports that a group of people
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Claude Mythos explained: Is Anthropic's most powerful AI model really too dangerous to release to the public?
Anthropic's Mythos AI is being kept behind closed doors as governments assess what faster, AI-driven vulnerability discovery means for cybersecurity. Anthropic's unveiling of its Claude Mythos Preview model alongside Project Glasswing is prompting widespread scrutiny as experts warn that the
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Anthropic's New Mythos A.I. Model Sets Off Global Alarms
Paul Mozur, based in Taipei, Taiwan, and Adam Satariano, in London, cover global technology issues. When Anthropic told the world this month that it had built an artificial intelligence model so powerful that it was too dangerous to release widely, the company named 11 organizations as partners to
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Anthropic's Mythos Model Is Being Accessed by Unauthorized Users
Anthropic is investigating the report of unauthorized access, and the company says it currently has no evidence that the access is impacting any of its systems. A small group of unauthorized users have accessed Anthropic PBC's new Mythos AI model, a technology that the company says is so powerful
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Unauthorized users gained access to Anthropic's restricted Mythos AI model
A small group communicating via a private Discord channel accessed Claude Mythos Preview by guessing the model's URL on the same day Anthropic announced Project Glasswing. Anthropic says it is investigating and has found no evidence of impact to its core systems. The breach highlights the risks of
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Some Unknown Group Is Reportedly Using Claude Mythos Without Permission
In a very cagily-written story from Bloomberg, Anthropic confirmed Tuesday that it has received a report that an unauthorized mystery group is accessing Claude Mythosâ€"the model it says is too dangerous to release. “We’re investigating a report claiming unauthorized access to Claude Mythos
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Anthropic reportedly 'lost control' of its most dangerous AI model -- and that should worry everyone
Just last week, Anthropic launched Claude Opus 4.7, described as a safer public-facing version of Claude Mythos, a model reportedly considered too dangerous for broad release. Now, the company is facing uncomfortable questions after reports claimed an unauthorized group gained access to Claude
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The Guardian view on Anthropic's Claude Mythos: when AI finds every flaw, who controls the internet? | Editorial
Tech can scale cyber-attacks and defences alike, raising questions about private power, public risk and the future of a shared internet Anthropic announced its latest AI model, Claude Mythos, this month but said it would not be released publicly, because it turns computers into crime scenes. The
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Discord group says it accessed Anthropic's unreleased Claude Mythos
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. Anthropic says Claude Mythos "is capable of identifying and then exploiting zero-day vulnerabilities in every major operating
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Mythos accessed by unauthorized users as Anthropic says 'We're investigating' -- Cracks may be showing in Project Glasswing as unknown users access model via third parties
* Unauthorized users claim to have access to Anthropic's Claude Mythos * The users gained access with guesswork and third-party access * The model is capable of exploiting software vulnerabilities at scale Anthropic's Mythos model, which is capable of spotting hundreds of zero-day
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Discord users breach access controls to reach Anthropic's Mythos model
This AI security breach shows why your data still needs protection A recent security incident involving Anthropic has highlighted just how fragile the safeguards around advanced AI systems can be. A Wired report suggests that a small group of users, operating through private Discord channels,
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Mythos access by Discord group reveals real danger of AI-powered hacking | Fortune
A Discord group's unauthorized access to Anthropic AI's powerful Mythos model is doing more than raising questions about the guardrails around powerful AI cybersecurity tools. It's exposing a bigger problem for the cybersecurity industry: AI can now find flaws and exploit them so quickly that
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Rogue Group Gains Access to Anthropic's Dangerous New Mythos AI
Remember Claude Mythos, Anthropic's new AI model that it hyped as being so powerful that it was too dangerous to release to the public? Well, it's already been broken into, according to new reporting from Bloomberg. A small group of Discord users gained access to a preview version of Mythos, a
[21]
Anthropic investigating possible breach of its Mythos AI model
Mary Cunningham is a reporter for CBS MoneyWatch. She previously worked at "60 Minutes," CBSNews.com and CBS News 24/7 as part of the CBS News Associate Program. Anthropic is investigating a possible breach of Mythos, a new model the artificial intelligence company rolled out to a small pool of
[22]
Unauthorised users hack Anthropic's 'too dangerous to release' AI
Hackers have gained access to Anthropic's Mythos, an AI the company considers too cybersecurity-sensitive to release publicly. A group of unauthorised users reportedly gained access to Anthropic's new product, which the artificial intelligence company says is too powerful to release to the public
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Anthropic probes unauthorized access to Mythos AI model
San Francisco (United States) (AFP) - American AI developer Anthropic said Tuesday it was investigating unauthorized access to Mythos, its powerful model which the company itself worries could be a boon for hackers. Anthropic said earlier this month it restricted the release of Mythos to 40 major
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What is Mythos AI and why could it be a threat to global cybersecurity?
Anthropic's decision to restrict access to its powerful new model increases fears about the advanced technology Anthropic has ruled out releasing its latest AI model, Mythos, to the public because of the threat it poses to global cybersecurity. However, the US tech startup behind the Claude
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Anthropic investigates unauthorized access to restricted Claude Mythos AI model - SiliconANGLE
Anthropic investigates unauthorized access to restricted Claude Mythos AI model Anthropic PBC is investigating a report that unauthorized users accessed Claude Mythos, the next-level artificial intelligence model the company says is powerful enough to enable dangerous cyberattacks. A small group
[26]
Anthropic probing reported Mythos leak on Discord
Bloomberg reports that users gained access to Mythos the same day Anthropic announced its limited release. A private Discord group has reportedly gained access to Anthropic's powerful new AI model Mythos, raising sharp concerns around the company's ability to keep the model on a short
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A group of users leaked Anthropic's AI model Mythos by reportedly guessing where it was located | Fortune
The AI model that Anthropic billed as too dangerous to release has reportedly been accessed by an unauthorized third party, and the incident raises concerns about the future of cybersecurity. The Mythos model was reportedly accessed by a handful of users in a private Discord chat on the day it was
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Anthropic investigates report of rogue access to hack-enabling Mythos AI
'Handful' of people allegedly gain unauthorised access to model adept at detecting cybersecurity vulnerabilities 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
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Former U.S. Cyber Director Sounds the Alarm on Anthropic's 'Too Powerful' AI Model
At the center of those concerns is the model's ability to identify and exploit software vulnerabilities at a level that rivals -- or exceeds -- top human experts. Anthropic itself has framed Mythos as part of a broader shift, noting that "AI models have reached a level of coding capability where
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2,000 flaws in 7 weeks? Anthropic's Mythos raises security alarms
Mythos AI cybersecurity risks explained: Anthropic's new AI model, Mythos, is a cybersecurity tool that has found thousands of software flaws. Its speed and ability to find vulnerabilities independently are changing the field. This powerful AI is not yet public due to its potential impact. The
[31]
Anthropic Investigates 'Unauthorized Access' to Its Ultra-Powerful Claude Mythos AI Model
A third party has reportedly already gained access to Anthropic's guarded Claude Mythos model. Claude Mythos is an advanced AI model developed by Anthropic that the company says has a level of coding ability that can "surpass all but the most skilled humans at finding and exploiting software
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Another Anthropic blunder? Did hackers get into its secret Mythos AI system -- raising fresh fears about deeper security gaps and powerful cyberattack risks worldwide
Another Anthropic blunder? Reports say a small unauthorized group accessed the secret Mythos AI cybersecurity tool. That tool is built to detect vulnerabilities and simulate advanced cyberattacks. Access was not meant for public use. It was restricted and tightly controlled. Early findings point to
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Uninvited Users Access Anthropic's Mythos AI Model | PYMNTS.com
By completing this form, you agree to receive marketing communications from PYMNTS and to the sharing of your information with our sponsor, if applicable, in accordance with our Privacy Policy and Terms and Conditions. That's according to a report Wednesday (April 22) by Bloomberg News, which
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Mythos AI accessed without approval via third-party vendor route
What Anthropic Has Said: Anthropic confirmed it is looking into the incident. "We're investigating a report claiming unauthorised access to Claude Mythos Preview through one of our third-party vendor environments," a company spokesperson said. The firm added that it has "no evidence" so far that
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Outsiders breached Anthropic's Claude Mythos same day 'potentially dangerous' AI model was revealed: report
A handful of users managed to gain unauthorized access to Anthropic's Claude Mythos - the model the company claims to be so dangerous that it would cause a wave of devastating cyberattacks if made available to the public. The breach occurred on April 8 - the same day that Anthropic and its CEO
[36]
Mythos Breach Shows Need for AI Framework, Magaziner
A small group of unauthorized users have accessed Anthropic PBC's new Mythos AI model, a technology that the company says is so powerful it can enable dangerous cyberattacks, according to a person familiar with the matter and documentation viewed by Bloomberg News. A handful of users in a private
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Anthropic investigates alleged unauthorised access to its Mythos AI model: Here is what happened
The group has been using Mythos since the day it was publicly announced. Anthropic recently introduced a cybersecurity-focused AI model called Mythos, describing it as a powerful tool designed to help enterprises detect and respond to digital threats. However, the company is now investigating
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Anthropic is investigating reports that unauthorized users gained access to Mythos, its restricted cybersecurity AI model, through a third-party vendor on the day of its announcement. The incident highlights vulnerabilities in controlled AI releases and raises questions about the model's actual capabilities versus the company's dramatic safety messaging.
Anthropic Investigates Unauthorized Access to Mythos AI Model
Anthropic is investigating a security breach involving Mythos, its highly restricted cybersecurity AI model designed exclusively for enterprise security applications. According to Bloomberg, a group of unauthorized users gained access to the AI model through a third-party vendor environment on the same day Anthropic publicly announced Project Glasswing, the controlled release program
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. The company confirmed it is examining claims of unauthorized access but stated that no evidence suggests the activity impacted Anthropic's core systems4
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Source: Market Screener
An Anthropic spokesperson told media outlets: "We're investigating a report claiming unauthorized access to Claude Mythos Preview through one of our third-party vendor environments"
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. The incident represents an awkward turn for a company that has built its brand on taking AI safety seriously while positioning Mythos as too dangerous for public release.How Unauthorized Users Accessed the Restricted Hacking Tool
The unauthorized group accessed Mythos through a combination of insider knowledge and predictable security patterns rather than sophisticated technical exploits. Members of a private Discord channel made "an educated guess about the model's online location based on knowledge about the format Anthropic has used for other models," Bloomberg reported
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. The group also leveraged access through a contractor who works for a third-party vendor evaluating Anthropic models.
Source: New York Post
Details about Anthropic's model hosting patterns were reportedly exposed in the recent Mercor data breach. Mercor, an AI staffing startup that supplies specialized contractors to major AI labs including Anthropic, was affected by a LiteLLM supply-chain attack earlier this month
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. Security researcher Lukasz Olejnik described this type of failure as "entirely imaginable" and something the cybersecurity industry has routinely dealt with for the last 20 years3
.The group provided evidence to Bloomberg in the form of screenshots and a live demonstration of the software, claiming they were "interested in playing around with new models, not wreaking havoc with them"
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.Project Glasswing and the Controlled Release Strategy
Mythos was released to a select number of vendors through Project Glasswing, including major technology companies like Apple, Amazon Web Services, Google, Microsoft, NVIDIA, and financial institutions like JPMorganChase
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. The limited release aimed to prevent weaponization by bad actors while allowing organizations to identify cybersecurity vulnerabilities in their own systems before criminals could exploit them.
Source: Mashable
According to Anthropic, Mythos can discover flaws in virtually any software and allegedly found "thousands of high- and critical-severity vulnerabilities" in operating systems and other software
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. The company warned that "the fallout -- for economies, public safety, and national security -- could be severe" if the model fell into the wrong hands.Mozilla reported that Mythos helped its team find 271 vulnerabilities in Firefox 150, though Mozilla CTO Bobby Holley noted that "we also haven't seen any bugs that couldn't have been found by an elite human researcher"
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. This assessment suggests the AI model excels at speed and thoroughness rather than discovering entirely novel vulnerability types.Related Stories
Supply-Chain Threats Expose Weaknesses in AI Security
The breach highlights critical vulnerabilities in controlled AI releases and supply-chain security. Security researcher Pia Hüsch from the Royal United Services Institute noted that while no company is ever completely secure and humans are often the weakest link, the incident "really illustrates how wide the circle of people who may be able to do this is, even if they don't have super technically sophisticated means"
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.Ram Varadarajan, CEO at deception-tech firm Acalvio, observed: "The Mythos breach didn't require a sophisticated attack. It just required a contractor, a URL pattern, and a day-one guess, which means the 'controlled release' model failed at its weakest link before the model's capabilities were ever the issue"
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.The fact that the breach was uncovered by a reporter rather than Anthropic raises questions about the company's monitoring capabilities. Security experts note that Anthropic should have the means to log and track model use, which should make it possible to stop unauthorized or malicious access, especially for a highly limited rollout
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.Scrutiny Over Mythos Capabilities and Marketing Hype
Early analysis from organizations with authorized access suggests Mythos may not be as revolutionary as Anthropic's messaging implied. Alan Woodward at the University of Surrey explained: "The AI is not necessarily capable of finding vulnerabilities that a human wouldn't, but it's just so much faster, thorough and relentless. Hence it's finding vulnerabilities that humans have missed"
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.The UK's AI Security Institute tested Mythos and found it capable of attacking only "small, weakly defended and vulnerable enterprise systems" with no indication that truly secure software or networks would be at significant risk, though the institute warned these capabilities are improving rapidly
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.Security expert Davi Ottenheimer characterized the situation as "a legitimate technological capability, reframed as civilisational threat, by a party that benefits from the reframing"
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. Tim Mackey from Black Duck noted that "Anthropic's marketing message for Mythos was effectively a challenge, not dissimilar to a capture-the-flag exercise, where success includes claims of unauthorized access to Mythos"5
.The incident underscores broader challenges in balancing AI development transparency with security concerns, particularly as organizations navigate vulnerability research in an era where AI models accelerate both offensive and defensive capabilities.
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