CVE-2026-59822

HIGH

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.

CVSS v3.1 Score

8.2
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
LOW
Availability
NONE
Published: 7/8/2026Modified: 9/3/2026

Related Intelligence (0)

No articles currently reference this CVE.

References (6)

https://github.com/BerriAI/litellm/commit/73869f0faf7d11ee21adcb5f91b8c33a340b6c2cPatchhttps://github.com/BerriAI/litellm/pull/26463Issue TrackingPatchhttps://github.com/BerriAI/litellm/releases/tag/v1.84.0ProductRelease Noteshttps://github.com/BerriAI/litellm/security/advisories/GHSA-7488-6r32-c95qMitigationPatchhttps://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-59822US Government Resourcehttps://www.wiz.io/blog/ai-infrastructure-honeypotThird Party Advisory