CVE-2026-54504 PUBLISHED

MCP Documentation Server: Web UI API binds to all interfaces without authentication by default

Assigner: GitHub_M
Reserved: 15.06.2026 Published: 17.09.2026 Updated: 17.09.2026

MCP Documentation Server is a local-first document management and semantic search server for AI coding agents. From 1.13.0 until 1.13.1, the automatically started Web UI in src/server.ts calls startWebServer in src/web-server.ts with START_WEB_UI enabled by default and WEB_PORT set to 3080. startWebServer uses app.listen(PORT) without a host, which binds the unauthenticated document-management API to all interfaces rather than localhost. A network-reachable client can invoke GET /api/documents, GET /api/documents/:id, POST /api/documents, POST /api/search-all, DELETE /api/documents/:id, and GET /api/config without credentials to enumerate and read documents, search the corpus, insert or delete documents, and tamper with the MCP assistant's knowledge base. The service must be reachable from the attacker's LAN, VM network, container bridge, VPN, or another routed network, and the issue does not provide remote code execution. This issue is fixed in 1.13.1.

Metrics

CVSS Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS Score: 8.8

Product Status

Vendor andrea9293
Product mcp-documentation-server
Versions
  • Version >= 1.13.0, < 1.13.1 is affected

References

Problem Types

  • CWE-306: Missing Authentication for Critical Function CWE
  • CWE-668: Exposure of Resource to Wrong Sphere CWE