Accenture contractor's personal Claude agent ran undetected on Pentagon network for two months

Earlier this year, a contractor for the consulting firm Accenture connected a secure, centralized system used by multiple intelligence agencies to a personal account for Claude Code, Anthropic’s AI coding assistant, according to a Wired report citing sources familiar with the incident. The contractor’s AI agent then sent the system’s login credentials to a third-party website that the National Institute of Standards and Technology has flagged as high risk, the sources said.

The network held controlled unclassified information, sensitive data that is not classified, covering topics such as critical infrastructure and biological-terrorism vulnerabilities, Wired reported. A source aware of the incident told the outlet that exposing login credentials “puts all the data that’s in there at risk” and could let an outsider log into a secure environment without anyone knowing.

The breach ran on NIPRNet, the Defense Department’s unclassified but tightly restricted internet-connected network, for two months before it was discovered and fixed, the sources said. Federal contractors are required to report cybersecurity incidents within 72 hours of discovery, but the sources told Wired that Accenture did not initially notify the government.

Accenture told Wired it had investigated the allegations “thoroughly and independently” and found them “without merit,” adding that the company “fully complied with our legal and contractual obligations.” When Wired pressed for detail, Accenture did not say who conducted the investigation or dispute that an incident had occurred. A Defense Department spokesperson said it does not comment on the status of its networks. Anthropic pointed Wired to its usage policy, which bars using its products to interfere with military infrastructure or bypass security controls without authorization; the Defense Department currently bars staff from using Claude.

Security experts told Wired the bigger risk lies beyond the stolen credentials. Jake Williams, a former NSA hacker now on the faculty of the security consultancy IANS, said unclassified information can become sensitive once pieced together, and that code tested on NIPRNet sometimes carries over into classified networks such as SIPRNet, the military’s air-gapped system for secret information. Matt Triner, founder of the Washington-based consultancy Hunter Strategy, said contractors face conflicting pressure to move fast while also securing their systems, calling incident reporting a legal duty that companies are nonetheless “often punished” for following.

Wired said there is no indication hackers reached a classified system, and the outlet withheld the name of the third-party website to avoid further exposure. Accenture holds more than $3.5 billion in federal contracts, including nearly $605 million with the Defense Department. The incident follows a separate case this month in which the FBI removed an Accenture contractor after an unpatched vulnerability let the hacking group ShinyHunters access the records of thousands of Bureau employees. Whether the Pentagon changes its contractor oversight or its rules on AI agents as a result has not been reported.