CVE-2026-59822

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 8.2 HIGH

8.2^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 4.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/BerriAI/litellm/commit/73869f0faf7d11ee21adcb5f91b8c33a340b6c2c	Patch
https://github.com/BerriAI/litellm/pull/26463	Issue Tracking Patch
https://github.com/BerriAI/litellm/releases/tag/v1.84.0	Product Release Notes
https://github.com/BerriAI/litellm/security/advisories/GHSA-7488-6r32-c95q	Mitigation Patch Vendor Advisory
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-59822	US Government Resource
https://www.wiz.io/blog/ai-infrastructure-honeypot	Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:litellm:litellm:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-07-08 20:16

Updated : 2026-09-03 13:05

NVD link : CVE-2026-59822

Mitre link : CVE-2026-59822

CVE.ORG link : CVE-2026-59822

JSON object : View

Products Affected

litellm

litellm

CWE

CWE-287

Improper Authentication

CWE-306

Missing Authentication for Critical Function

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