Anthropic's Mythos AI Cracked 'Almost All' US Classified Systems in Hours, NSA Chief Reportedly Said
NSA warns of Anthropic's AI model breaching US classified systems, prompting global security concerns
Bernadette B. TixonPublished 21 June 2026, 7:57 PM BST
Anthropic’s Mythos model allegedly penetrated nearly all classified networks ‘not in weeks, but in hours,’ according to Warner’s account of a direct briefing from NSA and Cyber Command leadership.
Anthropic's most powerful artificial intelligence model reportedly breached 'almost all' US classified systems in a matter of hours, according to Senator Mark Warner, who says the head of the National Security Agency told him directly that the model had penetrated nearly every classified system it was tested against. The claim has not been publicly confirmed by any government agency.
Senator Mark Warner, vice-chair of the Senate Intelligence Committee, said on 11 June that General Joshua Rudd, who leads both the NSA and the Pentagon's Cyber Command, told him directly that Anthropic's Mythos model 'broke into almost all of our classified systems, not in weeks, but in hours.' The extent of the alleged breach and which specific systems were affected have not been publicly disclosed. Anthropic did not respond to a request for comment.
https://www.ibtimes.co.uk/anthropic-ai-breach-us-classified-systems-1804084