CVE-2026-42208

CVE-2026-42208 is a critical-severity vulnerability in Litellm with a CVSS 3.x base score of 9.8. It is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, confirming it has been exploited in the wild (added 2026-05-08). The underlying weakness is classified as CWE-89.

Key facts

Description

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 access to the proxy and the credentials it manages. This issue has been patched in version 1.83.7.

Frequently asked questions

What is 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 access to the proxy and the credentials it manages. This issue has been patched in version 1.83.7.
How severe is CVE-2026-42208?
CVE-2026-42208 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-42208 being actively exploited?
Yes. CVE-2026-42208 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2026-05-08, which means active exploitation has been confirmed. It should be prioritised for remediation.
What products are affected by CVE-2026-42208?
CVE-2026-42208 affects Litellm. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-42208?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.
Does CVE-2026-42208 have an EU (EUVD) identifier?
Yes. CVE-2026-42208 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-28503. It is also flagged as exploited in the EUVD (since 2026-05-08).
When was CVE-2026-42208 published?
CVE-2026-42208 was published on 2026-05-08 and last updated on 2026-06-29.

References

Affected products (1)

More vulnerabilities in Litellm

All CVEs affecting Litellm →

Other CWE-89 (SQL Injection) vulnerabilities

Browse all CWE-89 (SQL Injection) vulnerabilities →