SECURELYN

CVE-2026-42208

LiteLLM is a proxy server (AI Gateway) to call LLM APIs in OpenAI (or native) format. From version 1.81.16 to before version 1.83.7, a database query used during proxy API key checks mixed the caller-supplied key value into the query text instead of passing it as a separate parameter. An unauthenticated attacker could send a specially crafted Authorization header to any LLM API route (for example POST /chat/completions) and reach this query through the proxy's error-handling path. An attacker could read data from the proxy's database and may be able to modify it, leading to unauthorised acces…

Scores

9.3
CVSS 9.3 out of 10, critical severity.
5.8%
EPSS 5.8% chance of exploitation in the next 30 days.

The facts

Published
8 May 2026
Last changed
15 July 2026
NVD status
Analyzed
Severity
Critical, CVSS 9.3 out of 10 (version 4.0)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/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…
Weakness
Affects
  • litellm litellm
Known exploited
Yes. CISA added it to the Known Exploited Vulnerabilities catalogue on 8 May 2026.
EPSS
5.8% chance of exploitation activity in the next 30 days (percentile 93).

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References