Vulnerability Description
LangBot is a global IM bot platform designed for LLMs. In version 4.10.7 and earlier, any authenticated user can add or change an STDIO MCP server configuration without an adequate authorization boundary. In src/langbot/pkg/provider/tools/loaders/mcp.py, StdioServerParameters accepts the configured command and arguments and starts a server-side subprocess on the LangBot server. An attacker who can sign up or obtain an account can use the Extensions MCP configuration to execute arbitrary commands with the privileges of the LangBot service, enabling data disclosure, modification, and service disruption. No fixed version is available as of this review.
CVSS Score
HIGH
Related Weaknesses (CWE)
References
- https://github.com/langbot-app/LangBot/security/advisories/GHSA-3pvh-63gf-j9mw
- https://www.ox.security/blog/mcp-supply-chain-advisory-rce-vulnerabilities-acros
FAQ
What is CVE-2026-54449?
CVE-2026-54449 is a vulnerability with a CVSS score of 8.8 (HIGH). LangBot is a global IM bot platform designed for LLMs. In version 4.10.7 and earlier, any authenticated user can add or change an STDIO MCP server configuration without an adequate authorization bound...
How severe is CVE-2026-54449?
CVE-2026-54449 has been rated HIGH with a CVSS base score of 8.8/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-54449?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.