LiteLLM: Authenticated command execution via MCP stdio test endpoints — CVE-2026-42271

Summary

### Impact 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…

Product

pip: litellm

What to do

General, cautious steps (verify details in the official source):

• Prioritize patching or mitigation immediately (treat as actively risky).
• Identify affected product versions in your inventory and verify whether you are impacted.
• Apply vendor patches/updates or recommended mitigations as soon as available.
• Read the official advisory for exact affected versions and remediation steps.

Official advisory

• Read the official source
• CVE Record
• NVD

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