AI Firm Mercor Confirms Breach as Hackers Claim 4TB of Stolen Data

Mercor confirmed it was affected by a late-March-2026 supply-chain compromise of the LiteLLM PyPI package, where attackers published malicious package versions for roughly 40 minutes; researchers warn of wide exposure due to millions of downloads and LiteLLM's presence in ~36% of cloud environments, and extortion group Lapsus$ subsequently listed Mercor claiming a 4TB data theft (unverified).