Improper Authentication in BerriAI litellm MCP Proxy Component
CVE-2026-12773

6.9MEDIUM

Key Information:

Vendor

Berriai

Status
Litellm
Vendor
CVE Published:
21 June 2026

Badges

👾 Exploit Exists🟡 Public PoC

What is CVE-2026-12773?

A vulnerability has been discovered in the BerriAI litellm's MCP Proxy that affects the UserAPIKeyAuth function within the user_api_key_auth_mcp.py file. This weakness can be exploited to achieve improper authentication, allowing unauthorized users to potentially gain access to privileged functions. The manipulation can be executed remotely, raising significant security concerns. Publicly available exploit information has been released, emphasizing the critical need for users of affected versions to implement necessary security measures as soon as possible.

Affected Version(s)

litellm 1.59.0

litellm 1.59.1

litellm 1.59.2

Exploit Proof of Concept (PoC)

PoC code is written by security researchers to demonstrate the vulnerability can be exploited. PoC code is also a key component for weaponization which could lead to ransomware.

CVE-2026-12773 - Proof of Concept

References

https://vuldb.com/vuln/372515
vdb-entrytechnical-description
https://vuldb.com/vuln/372515/cti
signaturepermissions-required
https://vuldb.com/cve/CVE-2026-12773
third-party-advisory

CVSS V4

Score:
6.9
Severity:
MEDIUM
Confidentiality:
Low
Integrity:
Low
Availability:
Low
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • 🟡

    Public PoC available

  • 👾

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

Credit

Eric-c (VulDB User)
VulDB CNA Team
.