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.
The record classifies CVE-2026-42208 under weakness class CWE-89. Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs no prior authentication, needs no user interaction, and has high impact on confidentiality, integrity, availability. 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 173 days ago.
Severity and exploitation probability
- CVSS v3.1 base score
- 9.8 — CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - CVSS v4.0 base score
- 9.3
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 - EPSS (FIRST)
- 5.7% probability of exploitation in the next 30 days, higher than 92.9% of all scored CVEs
- CISA KEV
- Listed since 2026-05-08, federal remediation deadline 2026-05-11 — used in known ransomware campaigns
- Threadlinqs priority
- 10/10 — CISA lists it as used in ransomware, which Threadlinqs scores at the maximum
- Published
- 2026-05-08, last modified 2026-07-15
Is CVE-2026-42208 being exploited?
CISA added CVE-2026-42208 to the Known Exploited Vulnerabilities catalog on 2026-05-08, which means the agency holds evidence of exploitation in the wild; US federal civilian agencies had to remediate it by 2026-05-11 under BOD 22-01. CISA flags the vulnerability as one used in known ransomware campaigns. Weaponised exploit code for CVE-2026-42208 is publicly available. 6 public proof-of-concept repositories are tracked for this identifier. A ProjectDiscovery Nuclei detection template exists (http/cves/2026/CVE-2026-42208.yaml). It currently carries a trending score of 53 in the Threadlinqs vulnerability feed.
- ridhinva/litellm-sqli-scanner (github)
- imjdl/CVE-2026-42208_lab (github)
- 0xBlackash/CVE-2026-42208 (github)
- Zeltoc/threat-intel-brief-cve-2026-42208-litellm (github)
- rootdirective-sec/CVE-2026-42208-Lab (github)
- HAERIN-L/poc_cve-2026-42208 (github)
Affected products and versions
- Litellm: Litellm
Affected software packages:
pip:litellm— patched in 1.83.7
How to fix CVE-2026-42208
The record marks a vendor fix as available for CVE-2026-42208. Fixed versions are recorded for 1 package: pip:litellm 1.83.7. Patch reference: https://github.com/BerriAI/litellm/security/advisories/GHSA-r75f-5x8p-qvmc. Vendor advisory: https://github.com/BerriAI/litellm/security/advisories/GHSA-r75f-5x8p-qvmc. Because CVE-2026-42208 is KEV-listed, US federal civilian agencies were required to apply the vendor fix, or stop using the product, by 2026-05-11. Apply the vendor fix referenced above to every affected product listed in this record, then confirm the running version against the vendor advisory.
Threat activity tracking CVE-2026-42208
2 tracked threats in the Threadlinqs corpus reference CVE-2026-42208, either in the campaign’s CVE list or as an indicator on the campaign record.
Sources
Enriched from CVE.org, NVD, FIRST EPSS, CISA KEV, GitHub Security Advisories, public proof-of-concept repositories, ProjectDiscovery Nuclei. Last verified by Threadlinqs on . This product uses the NVD API but is not endorsed or certified by the NVD.