AI Agent Supply Chain Attacks: What the LiteLLM Breach Means for Your Stack

The morning of March 31, 2026, started badly for the AI ecosystem. A malicious actor had slipped compromised versions of LiteLLM - one of the most widely-deployed LLM proxy libraries in production - onto PyPI. The poisoned packages were live for 40 minutes. That was enough. Mercor, the AI-powered hiring platform backed by top-tier VCs, disclosed it had been hit. And Wiz's cloud scanning data made the scale immediately clear: LiteLLM is present in 36% of cloud environments. ~500,000 machines reached. This wasn't a niche tool getting exploited. This was the supply chain for AI.