CVE-2026-35030

LiteLLM is a proxy server (AI Gateway) to call LLM APIs in OpenAI (or native) format. Prior to 1.83.0, when JWT authentication is enabled (enable_jwt_auth: true), the OIDC userinfo cache uses token[:20] as the cache key. JWT headers produced by the same signing algorithm generate identical first 20 characters. This configuration option is not enabled by default. Most instances are not affected. An unauthenticated attacker can craft a token whose first 20 characters match a legitimate user's cached token. On cache hit, the attacker inherits the legitimate user's identity and permissions. This affects deployments with JWT/OIDC authentication enabled. Fixed in v1.83.0.

CVSS v3 9.1 CRITICAL

9.1^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/BerriAI/litellm/security/advisories/GHSA-jjhc-v7c2-5hh6	Vendor Advisory Mitigation

Configurations

Configuration 1 (hide)

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

History

07 Apr 2026, 20:20

Type	Values Removed	Values Added
References	~~() https://github.com/BerriAI/litellm/security/advisories/GHSA-jjhc-v7c2-5hh6 -~~	() https://github.com/BerriAI/litellm/security/advisories/GHSA-jjhc-v7c2-5hh6 - Vendor Advisory, Mitigation
First Time		Litellm litellm Litellm
CPE		cpe:2.3:a:litellm:litellm::::::::

07 Apr 2026, 15:17

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 9.1

06 Apr 2026, 17:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-04-06 17:17

Updated : 2026-04-07 20:20

NVD link : CVE-2026-35030

Mitre link : CVE-2026-35030

CVE.ORG link : CVE-2026-35030

JSON object : View

Products Affected

litellm

litellm

CWE

CWE-287

Improper Authentication

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