CVE-2026-12773
criticalpriority · track · 39EPSS 0.010 · 63 %ileEUUSEPSS · scored 2026-10-27
A weakness has been identified in BerriAI litellm up to 1.59.8. Affected is the function UserAPIKeyAuth of the file litellm/proxy/_experimental/mcp_server/auth/user_api_key_auth_mcp.py of the component MCP Proxy. Executing a manipulation can lead to improper authentication. The attack may be launched remotely. The exploit has been made available to the public and could be used for attacks. The vendor was contacted early about this disclosure.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–critical · 2.7–9.8
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (11)
Products and version ranges known to be affected.
advisories (2)
Vendor and ecosystem advisories describing this.
- GHSA-4jcj-7x88-m979LiteLLM: MCP Proxy Has Improper Authentication2026-06-21ghsa · osvUS
A weakness has been identified in BerriAI litellm up to 1.59.8. Affected is the function UserAPIKeyAuth of the file litellm/proxy/_experimental/mcp_server/auth/user_api_key_auth_mcp.py of the component MCP Proxy. Executing a manipulation can lead to improper authentication. The attack may be launched remotely. The exploit has been made available to the public and could be used for attacks. The vendor was contacted early about this disclosure.
- PYSEC-2026-4067LiteLLM: MCP Proxy Has Improper Authentication2026-10-01vendor · osvUS
A weakness has been identified in BerriAI litellm up to 1.59.8. Affected is the function UserAPIKeyAuth of the file litellm/proxy/_experimental/mcp_server/auth/user_api_key_auth_mcp.py of the component MCP Proxy. Executing a manipulation can lead to improper authentication. The attack may be launched remotely. The exploit has been made available to the public and could be used for attacks. The vendor was contacted early about this disclosure.
also known as (5)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (19)
External citations — patches, advisories, analysis.
- https://gist.github.com/YLChen-007/3cfaad10a69d7a15e4d4d458cb53309ecnnvd
- https://github.com/BerriAI/litellm/releasesPatchcnnvd
- https://vuldb.com/cve/CVE-2026-12773cnnvd
- https://vuldb.com/submit/811282cnnvd
- https://vuldb.com/vuln/372515cnnvd
- https://vuldb.com/vuln/372515/cticnnvd
- https://gist.github.com/YLChen-007/3cfaad10a69d7a15e4d4d458cb53309eenisa_euvd
- https://vuldb.com/cve/CVE-2026-12773enisa_euvd
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