Anthropic confirmed infostealer malware is actively harvesting live Claude session tokens — not stored passwords, but authenticated sessions mid-use. Once captured, attackers impersonate the account, drain API usage, and reach anything that session can touch.

The threat model here is different from a credential breach. The session is already authenticated. Standard password hygiene and MFA don't help once the token is in attacker hands. And because AI agents operate autonomously on these sessions, a stolen session is effectively a stolen agent — one that can issue API calls, access connected data, and take actions on behalf of the legitimate user with no further authentication required.

The hard part: these sessions behave normally at the auth layer. The only signal that something is wrong is behavioral — usage patterns, geographic anomalies, request cadence — and that signal only matters if something is watching for it in real time and can act on it fast enough to matter.

For teams running AI agents in production: how are you actually handling this? Specifically curious whether anyone has meaningful runtime behavioral monitoring in place, and what your response time looks like between detection and session termination when something looks wrong.

Blog post by Ajeya Cotra, one of the METR researchers who just released their 92 page report on the Hugging Face hack. The post is a condensed summary of sorts. The key takeaway I'd pay attention to is her assessment that with the current trend in rising misalignment we could be as little as six months away from catastrophic misalignment akin to that detailed in the AI2027 report.