In mid-September 2025, we detected suspicious activity that later investigation determined to be a highly sophisticated espionage campaign. The attackers used AI’s “agentic” capabilities to an unprecedented degree—using AI not just as an advisor, but to execute the cyberattacks themselves.

In Phase 1, the human operators chose the relevant targets (for example, the company or government agency to be infiltrated). They then developed an attack framework—a system built to autonomously compromise a chosen target with little human involvement. This framework used Claude Code as an automated tool to carry out cyber operations.

At this point they had to convince Claude—which is extensively trained to avoid harmful behaviors—to engage in the attack. They did so by jailbreaking it, effectively tricking it to bypass its guardrails. They broke down their attacks into small, seemingly innocent tasks that Claude would execute without being provided the full context of their malicious purpose. They also told Claude that it was an employee of a legitimate cybersecurity firm, and was being used in defensive testing.

The attackers then initiated the second phase of the attack, which involved Claude Code inspecting the target organization’s systems and infrastructure and spotting the highest-value databases. Claude was able to perform this reconnaissance in a fraction of the time it would’ve taken a team of human hackers. It then reported back to the human operators with a summary of its findings.

In the next phases of the attack, Claude identified and tested security vulnerabilities in the target organizations’ systems by researching and writing its own exploit code. Having done so, the framework was able to use Claude to harvest credentials (usernames and passwords) that allowed it further access and then extract a large amount of private data, which it categorized according to its intelligence value. The highest-privilege accounts were identified, backdoors were created, and data were exfiltrated with minimal human supervision.

In a final phase, the attackers had Claude produce comprehensive documentation of the attack, creating helpful files of the stolen credentials and the systems analyzed, which would assist the framework in planning the next stage of the threat actor’s cyber operations.

Claude didn’t always work perfectly. It occasionally hallucinated credentials or claimed to have extracted secret information that was in fact publicly-available. This remains an obstacle to fully autonomous cyberattacks.