An AI model so good at finding software vulnerabilities that the US government pulled the plug on foreign access. That’s the backdrop to French President Emmanuel Macron’s push at the G7 summit to restore allied nations’ ability to use Anthropic’s Mythos, a frontier AI system that has become both a prized cybersecurity tool and a geopolitical flashpoint.
On June 17, Macron said he expected progress “in weeks” on expanding non-US access to advanced American AI models. The statement came at the tail end of a three-day G7 summit where AI dominated conversations nearly as much as traditional economic coordination.
What happened and why it matters
Around June 13, Anthropic disabled global access to its two most advanced models, Mythos 5 and Fable 5, following what the company described as compliance with a US government directive citing national security concerns. No formal export control notification had been issued by mid-June. The restrictions instead arose from internal compliance measures Anthropic took in response to government pressure.
The reason is Mythos itself. By June 2026, the model had demonstrated the ability to autonomously identify thousands of zero-day vulnerabilities, the kind of undiscovered software flaws that intelligence agencies and cybercriminals alike would pay fortunes to exploit.
