CVE-2026-12773mediumCWE-287CWE-303

CVE-2026-12773: medium-severity vulnerability in BerriAI litellm

BerriAI litellm MCP Proxy user_api_key_auth_mcp.py UserAPIKeyAuth improper authentication

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33Vexday Risk Score

No sign of exploitation. It has a public proof of concept.

ssvc Attendcvss 6.9epss 1.0%
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:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P
Affected products
BerriAI · litellm
⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.
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