Pierluigi Paganini
April 08, 2026
Anthropic has unveiled Claude Mythos, a new AI model designed to strengthen cybersecurity through Project Glasswing, aiming to secure critical software before it can be abused.
Interest in Mythos grew after a leak of nearly 3,000 internal files revealed details of the project, which Anthropic later confirmed. The company has now officially introduced Mythos Preview, positioning it as a major step forward in AI, powerful, but potentially risky if it falls into the wrong hands.
Anthropic says Claude Mythos is a major leap beyond its Haiku, Sonnet, and Opus models, introducing a new top tier called Copybara. It stands out for strong agentic coding and reasoning skills, achieving top scores in software tasks and enabling advanced cybersecurity capabilities.
Project Glasswing is a joint effort led by Anthropic with major tech and security firms (Amazon Web Services, Anthropic, Apple, Broadcom, Cisco, CrowdStrike, Google, JPMorganChase, Linux Foundation, Microsoft, NVIDIA, and Palo Alto Networks) to protect critical software using advanced AI.
It leverages Claude Mythos Preview, a powerful model capable of finding and exploiting vulnerabilities at a level beyond most humans.
The goal is to use these capabilities defensively, helping organizations detect and fix flaws before attackers can exploit them. Anthropic is sharing access with partners and funding the initiative to strengthen both proprietary and open-source software security.
“AI capabilities have crossed a threshold that fundamentally changes the urgency required to protect critical infrastructure from cyber threats, and there is no going back. Our foundational work with these models has shown we can identify and fix security vulnerabilities across hardware and software at a pace and scale previously impossible. That is a profound shift, and a clear signal that the old ways of hardening systems are no longer sufficient.” said Anthony Grieco, SVP & Chief Security & Trust Officer, Cisco. “Providers of technology must aggressively adopt new approaches now, and customers need to be ready to deploy. That is why Cisco joined Project Glasswing—this work is too important and too urgent to do alone.”
While Anthropic develops AI for broader scientific goals, it recognizes the risk of abuse, especially after observing early AI-driven cyber espionage campaigns. The concern is that such capabilities could soon enable faster and more advanced attacks than defenders can handle.
“Mythos Preview has already found thousands of high-severity vulnerabilities, including some in every major operating system and web browser. Given the rate of AI progress, it will not be long before such capabilities proliferate, potentially beyond actors who are committed to deploying them safely.” reads the announcement by Anthropic. “The fallout—for economies, public safety, and national security—could be severe. Project Glasswing is an urgent attempt to put these capabilities to work for defensive purposes.”
Glasswing brings together major tech and security companies to use Mythos defensively, helping secure critical software and infrastructure. Anthropic plans to limit access for now, hoping to improve global cybersecurity before such powerful tools become widely available.
Modern software underpins critical systems like banking, healthcare, energy, and government, but it has always contained vulnerabilities—some severe enough to enable cyberattacks, data theft, and disruption. These threats are already costly and widespread, with global cybercrime estimated at around $500 billion annually and often driven by state-backed actors.
With advanced AI models like Claude Mythos, the effort and expertise needed to find and exploit flaws has dropped sharply. These models can identify long-hidden vulnerabilities and develop sophisticated exploits, sometimes outperforming human experts. This raises serious risks, as attacks could become faster, more frequent, and more damaging.
However, the same capabilities can be used defensively. Initiatives like Project Glasswing aim to harness AI to detect and fix vulnerabilities at scale, helping secure critical infrastructure. The challenge now is to deploy these tools responsibly and quickly, ensuring defenders stay ahead in an AI-driven cybersecurity landscape.
Anthropic is investing $100M in usage credits and funding open-source security projects, while sharing findings to improve industry-wide defenses. The initiative aims to expand collaboration across tech, security, and governments to develop best practices and strengthen cybersecurity in the AI era.
“We are hopeful that Project Glasswing can seed a larger effort across industry and the public sector, with all parties helping to address the biggest questions around the impact of powerful models on security. We invite other AI industry members to join us in helping to set the standards for the industry.” concludes the report. “In the medium term, an independent, third-party body—one that can bring together private- and public-sector organizations—might be”
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