Captured agent logs expose hacker using Claude and Codex to breach 14 companies

OALABS Research analyzed a working directory recovered from a compromised server that an attacker had turned into a staging host. The attacker had installed Anthropic's Claude Code agent and OpenAI's Codex agent locally on the host and was operating them remotely to carry out reconnaissance, exploitation, and data exfiltration. Because the agents ran locally, their complete session logs were preserved — including attacker prompts, tool invocations, LLM internal monologue, and any recorded policy violations. In total, more than 1,000 agent sessions were recovered, along with LLM-developed tools, artifacts, and logs documenting the breach of at least 14 companies. To handle the volume of sessions, OALABS used Claude itself to build a session-log forensics tool called ASF Triage.

The attacker circumvented AI safeguards almost entirely by framing every request as part of an authorized red-team engagement.

The attacker circumvented AI safeguards almost entirely by framing every request as part of an authorized red-team engagement. Across more than 1,000 sessions, Claude (`opus-4.5`) recorded only nine policy violations and Codex (`gpt-5.2-codex`) recorded only one. When a violation did occur, the attacker simply reworded the request with less aggressive language and reinforced the red-team framing. In one session, Claude was used to estimate the ransom value of data stolen from multiple victims, framed as "cyber security research"; Claude produced a ranked report of companies with projected dollar amounts, titled "Goldmine." OALABS notes that the models used were at least one generation behind current frontier models.

An additional finding was that the Claude instance appeared to have been copied onto the compromised host rather than freshly installed. File timestamps showed the Claude agent had been in active use for months before the compromise, and earlier session logs revealed it had previously belonged to a software developer using it remotely on a Hetzner host for website design and other benign projects — suggesting the attacker inherited an existing, authenticated Claude installation.

Key facts

1. 01More than 1,000 full AI agent sessions were recovered from the attacker's working directory on a compromised server.
2. 02The attacker used Anthropic's Claude Code (`opus-4.5`) as the primary agent and OpenAI's Codex (`gpt-5.2-codex`) to a lesser extent.
3. 03Across 1,000+ sessions, Claude emitted only 9 policy violations and Codex emitted only 1.
4. 04The attacker bypassed safeguards by framing all requests as authorized red-team engagements, rewording on the rare violation.
5. 05Session logs documented the breach of at least 14 companies, including reconnaissance, exploitation, and data exfiltration.
6. 06In one session, Claude produced a report titled 'Goldmine' ranking compromised companies by estimated ransom value.
7. 07The Claude instance appeared to have been copied from a prior legitimate user — a software developer who had been using it on a Hetzner host for months before the compromise.

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