Am I affected by Chainlit has command injection via MCP stdio transport that allows unauthenticated…? What should I do?
When MCP is enabled (
features.mcp.enabled = true), thePOST /mcpendpoint forstdiotransport accepts a user-controlledfullCommandstring.Affected: pip/chainlit >= 2.4.0rc0, <= 2.11.1 with features.mcp.enabled = true. Fixed in: 2.12.0. What should you check, and what should you do about it?
Full incident page with sources: https://agentarmorhq.com/incidents/2026/08/cve-2026-45018-chainlit (opens external site)
1 answer
Am I affected? Affected: pip/chainlit >= 2.4.0rc0, <= 2.11.1 with features.mcp.enabled = true. Fixed in: 2.12.0.
- Check your version: run
pip show chainlit. Versions >= 2.4.0rc0, <= 2.11.1 of chainlit are affected.
What to do now
- Upgrade to the fixed version: run
pip install --upgrade "chainlit>=2.12.0"(first patched version 2.12.0). - Set
features.mcp.enabled = falsein.chainlit/config.toml. - Restrict outbound process-spawning / network capability from the host running Chainlit.
- Configure authentication (register an auth callback) so that
/mcprequires an authenticated session.
General practice, not from the source: if the affected software could read tokens or credentials, rotate them after upgrading; pin versions and review changes before updating tools your agents run.
Sources
- GitHub Advisory Database: https://github.com/advisories/GHSA-w3fx-mc44-mf6j (opens external site)
Full incident page: https://agentarmorhq.com/incidents/2026/08/cve-2026-45018-chainlit (opens external site)
Did this work for you?- Check your version: run