CVE-2026-12773
HIGH severity · CVSS 7.3 · Improper authentication
7.3CVSS HIGH
Summary
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.
Impact & exploitability
Attack vectorNetwork
Attack complexityLow
Privileges requiredNone
User interactionNone
Confidentiality impactLow
Integrity impactLow
Availability impactLow
Exploit probability (EPSS)1%
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
Affected products we track (1)
Recommendation
Apply the vendor fix promptly. Open any affected product above for its exact safe version.
Additional information
- NVD record
- https://vuldb.com/cve/CVE-2026-12773Advisory
- https://vuldb.com/vuln/372515Advisory
- https://vuldb.com/vuln/372515/cti
- https://access.redhat.com/security/cve/CVE-2026-12773
- https://bugzilla.redhat.com/show_bug.cgi?id=2491112
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-12773.json
- https://gist.github.com/YLChen-007/3cfaad10a69d7a15e4d4d458cb53309eAdvisory
- https://vuldb.com/submit/811282Advisory