CVE-2026-59822

Aliases:GHSA-7488-6r32-c95qPYSEC-2026-3479
Analyzed
Published: 08 Jul 2026, 19:32
Last modified:02 Sept 2026, 19:58

Vulnerability Summary

Overall Risk (default)
medium
35/100
CVSS Score
8.8 HIGH
v4.0 (cve.org)
EPSS Score
0.52% LOW
1% probability 0.00%
KEV
Listed
CISA
1 listing
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

08 Jul 2026, 19:32
Published
Vulnerability first disclosed
02 Sept 2026, 00:00
Added to CISA KEV
BerriAI LiteLLM Improper Authentication Vulnerability
02 Sept 2026, 19:58
Last Modified
Vulnerability information updated
16 Sept 2026, 00:00
CISA Remediation Due
Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.

Description

LiteLLM is a proxy server (AI Gateway) to call LLM APIs in OpenAI (or native) format. Prior to 1.84.0, LiteLLM's MCP Streamable HTTP endpoint allowed an unauthenticated attacker to use a fabricated Authorization header to trigger an OAuth2 passthrough fallback path that replaced failed LiteLLM key validation with an empty UserAPIKeyAuth() object, allowing requests to reach MCP tooling without a valid LiteLLM key. This issue is fixed in version 1.84.0.

CVSS Metrics

  • v4.0•HIGH•Score: 8.8CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N
  • v4.0•HIGH•Score: 8.8CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
  • v3.1•HIGH•Score: 8.2CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N

EPSS Trends

Current EPSS score: 0.52%• Percentile: 42%

Techniques & Countermeasures

  • CWE-287•Improper Authentication

    When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.

  • CWE-306•Missing Authentication for Critical Function

    The product does not perform any authentication for functionality that requires a provable user identity or consumes a significant amount of resources.

Affected Systems

  • berriai•litellm

    < 1.84.0

  • litellm•litellm

    < 1.84.0

  • PyPI•litellm

    < 1.84.0

References (10)