The European Union Agency for Cybersecurity, known as ENISA, has become the first EU body to gain access to Anthropic’s Mythos AI model. Testing began on September 10, 2026, following months of negotiations that were complicated by US export controls on advanced AI technologies.
The access agreement positions Europe’s primary cybersecurity authority to evaluate what Anthropic describes as a defensively oriented AI system, one that has already demonstrated some eyebrow-raising capabilities during earlier testing phases with other partners.
What Mythos actually does
Mythos is primarily designed for defensive cybersecurity applications. During preliminary testing, the model autonomously identified over 10,000 zero-day vulnerabilities. Zero-days are software flaws that vendors don’t yet know about, the kind of weaknesses that nation-state hackers and criminal groups pay millions to exploit.
The model also reportedly achieves success rates exceeding 83% in generating effective exploits on its first attempt. That’s a significant leap over previous models like Opus 4.6.
The ENISA arrangement grew out of Project Glasswing, Anthropic’s structured rollout program for Mythos access. That project kicked off in April 2026 with roughly 50 organizations, most of them US-based. By June, the partner list had swelled by an additional 150 organizations spanning more than 15 countries.
Why the EU deal matters
Negotiations between Anthropic and ENISA reportedly started in early June 2026, but the path to actual testing wasn’t straightforward. US export controls on sophisticated AI technologies created friction.
Project Glasswing already included partners from France, Germany, and Italy, along with NATO. Adding the EU’s dedicated cybersecurity agency to that list gives the collaboration an institutional anchor it didn’t previously have.
Anthropic’s growing footprint
The ENISA deal arrives as Anthropic has filed for an IPO following a massive $65 billion funding round that pushed its valuation toward the $1 trillion mark.
Project Glasswing’s rapid growth from 50 to over 200 partners in just a few months suggests strong demand for Mythos-level capabilities, particularly among entities responsible for defending critical systems.