CVE-2026-59822

Summary

LiteLLM is a proxy server (AI Gateway) to call LLM APIs in OpenAI (or native) format. Prior to 1.84.0, LiteLLM's MCP Streamable HTTP endpoint allowed an unauthenticated attacker to use a fabricated Authorization header to trigger an OAuth2 passthrough fallback path that replaced failed LiteLLM key validation with an empty UserAPIKeyAuth() object, allowing requests to reach MCP tooling without a valid LiteLLM key. This issue is fixed in version 1.84.0.

Affected Software

VendorProductVersion RangeStatus
BerriAIlitellm< 1.84.0affected

Weaknesses

  • CWE-287: CWE-287: Improper Authentication
  • CWE-306: CWE-306: Missing Authentication for Critical Function

References