{"id":"CVE-2026-55605","revision":"7486667e174c411d8040fa427ce4408e","records":[{"revision":"7486667e174c411d8040fa427ce4408e","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-55605","aliases":[],"title":"@arikusi/deepseek-mcp-server Missing Authentication on Self-Hosted HTTP MCP Endpoint","description":"DeepSeek MCP Server is an MCP server for DeepSeek V4. Starting in version 1.4.2 and prior to version 1.8.0, the self-hosted HTTP transport of `@arikusi/deepseek-mcp-server` exposes `POST /mcp` without any authentication: `createMcpExpressApp` is called without an `authProvider` and no middleware guards the route, so any network-reachable client can issue an unauthenticated `initialize` request and obtain a valid MCP session identifier. In reproduced testing against commit `5e1302171e99`, an unauthenticated client was able to initialize a session, enumerate tools, and invoke the local `deepseek_sessions` tool with no credentials. The same unauthenticated session also exposes `deepseek_chat`, whose handler uses the server-side `DEEPSEEK_API_KEY` when self-hosted deployments configure one. This issue applies to self-hosted HTTP mode, not the separately documented hosted BYOK endpoint in `README.md`, which expects an `Authorization: Bearer ...` header. Upstream self-hosted container assets enable HTTP mode by default (`Dockerfile`) and publish port `3000` (`docker-compose.yml`). Version 1.8.0 contains a patch for this issue.","state":0,"publishedAt":"2026-07-09T21:10:53.882+00:00","modifiedAt":"2026-07-10T13:35:30.01+00:00","affected":[{"ecosystem":"Vendor product","name":"deepseek-mcp-server","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"arikusi\",\n                    \"product\": \"deepseek-mcp-server\",\n                    \"versions\": [\n                        {\n                            \"version\": \">= 1.4.2, < 1.8.0\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","score":5.3,"severity":"MEDIUM"}],"references":["https://github.com/arikusi/deepseek-mcp-server/security/advisories/GHSA-72f3-6w86-7rv3","https://github.com/arikusi/deepseek-mcp-server/blob/main/CHANGELOG.md#180---2026-06-14","https://github.com/arikusi/deepseek-mcp-server/releases/tag/v1.8.0"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-55605","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-55605","identifiers":["CVE-2026-55605"]},"retained":false,"historicalAffected":[]}],"coverage":[]}