8.8

CVE-2026-59822

LiteLLM: MCP Authentication Bypass via OAuth2 Passthrough Fallback

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.
Daten sind bereitgestellt durch National Vulnerability Database (NVD)
Litellm ≫ Litellm Version < 1.84.0
Zu dieser CVE wurde keine Warnung gefunden.
EPSS Metriken
Typ Quelle Score Percentile
EPSS FIRST.org 0.3% 0.226
CVSS Metriken
Quelle Base Score Exploit Score Impact Score Vector String
NIST 8.2 3.9 4.2
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N
security-advisories@github.com 8.8 0 0
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CWE-287 Improper Authentication

When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.

CWE-306 Missing Authentication for Critical Function

The product does not perform any authentication for functionality that requires a provable user identity or consumes a significant amount of resources.

https://github.com/BerriAI/litellm/security/advisories/GHSA-7488-6r32-c95q
Patch
Vendor Advisory
Mitigation
https://github.com/BerriAI/litellm/pull/26463
Patch
Issue Tracking
https://github.com/BerriAI/litellm/commit/73869f0faf7d11ee21adcb5f91b8c33a340b6c2c
Patch
https://github.com/BerriAI/litellm/releases/tag/v1.84.0
Product
Release Notes