What is CVE-2026-42271?
LiteLLM is a proxy server (AI Gateway) to call LLM APIs in OpenAI (or native) format. From version 1.74.2 to before version 1.83.7, two endpoints used to preview an MCP server before saving it — POST /mcp-rest/test/connection and POST /mcp-rest/test/tools/list — accepted a full server configuration in the request body, including the command, args, and env fields used by the stdio transport. When called with a stdio configuration, the endpoints attempted to connect, which spawned the supplied command as a subprocess on the proxy host with the privileges of the proxy process. The endpoints were gated only by a valid proxy API key, with no role check. Any authenticated user — including holders of low-privilege internal-user keys — could therefore run arbitrary commands on the host. This issue has been patched in version 1.83.7.
Timeline
- 2026-05-08Published to the U.S. National Vulnerability Database (NVD)
- 2026-06-08Added to the CISA Known Exploited Vulnerabilities (KEV) catalog
- 2026-06-22CISA federal remediation deadline (BOD 22-01)
- 2026-07-15NVD record last updated
CISA Known Exploited Vulnerability
BerriAI LiteLLM Command Injection Vulnerability
Affected product
BerriAI LiteLLM
NVD also lists CPE entries for: Litellm, Redhat Openshift Ai
Remediation Steps
- Check CISA's Known Exploited Vulnerabilities catalog for product-specific guidance
- Contact vendor for available security patches
- Apply patch or implement recommended mitigations from vendor advisory
- Verify patch installation and monitor for indicators of active exploitation
References
- https://github.com/BerriAI/litellm/security/advisories/GHSA-v4p8-mg3p-g94g
- https://access.redhat.com/errata/RHSA-2026:27784
- https://access.redhat.com/errata/RHSA-2026:28960
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-42271
- https://github.com/BerriAI/litellm/releases/tag/v1.83.7-stable
- https://nvd.nist.gov/vuln/detail/CVE-2026-42271
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog
Referenced in our briefings & reports
- Vulnerability Priority Report – Week 1 of July 2026 (July 6 – 12)
- Vulnerability Priority Report – Week 5 of June 2026 (June 29 – July 5)
- Vulnerability Priority Report – Week 4 of June 2026 (June 22 – 28)
- Vulnerability Priority Report – Week 3 of June 2026 (June 15 – 21)
- Vulnerability Priority Report – Week 2 of June 2026 (June 8 – 14)
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