{"id":"CVE-2026-111767","aliases":["GHSA-22jm-h49p-29qw"],"url":"https://o3.security/vulnerability/CVE-2026-111767","summary":"MCP TypeScript SDK: Experimental tasks were not tied to the session that created them","details":"### Summary\nIn affected versions, the experimental tasks feature (`taskStore`) did not check which session created a task. Clients sharing one `InMemoryTaskStore` could list, read and cancel each other's tasks.\n\nExperimental tasks are deprecated. The 2026-07-28 specification replaced them with a redesigned extension. The best course of action is to stop using them.\n\n### Am I affected?\nOnly if your HTTP server passes `taskStore` to `McpServer` or `Server`. If `grep -ri taskstore --exclude-dir=node_modules .` finds nothing, you are not affected.\n\nAffected versions: `@modelcontextprotocol/sdk` 1.24.0 through 1.31.0. The 2.x packages are not affected.\n\n### Fix\nUpgrade to `@modelcontextprotocol/sdk` 1.32.0 or later. Each task is now tied to the session that created it, so a client that starts a new session can no longer reach its earlier tasks.\n\nIf you cannot upgrade yet, remove `taskStore`, or create one `InMemoryTaskStore` per session.","published":"2026-10-20T18:28:45.650Z","modified":"2026-10-24T02:50:10.551479324Z","cvss":{"score":8.6,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:L"},"epss":null,"cisaKev":null,"exploitsKnown":null,"affectedPackages":[{"ecosystem":"npm","name":"@modelcontextprotocol/sdk","fixedVersion":"1.32.0"}],"fix":{"url":"https://github.com/modelcontextprotocol/typescript-sdk/commit/727075b5bbeb77fbea22041b36b72a73042160fa","label":"modelcontextprotocol/typescript-sdk@727075b"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/111xxx/CVE-2026-111767.json"},{"type":"ADVISORY","url":"https://github.com/modelcontextprotocol/typescript-sdk/security/advisories/GHSA-22jm-h49p-29qw"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-111767"},{"type":"FIX","url":"https://github.com/modelcontextprotocol/typescript-sdk/commit/727075b5bbeb77fbea22041b36b72a73042160fa"},{"type":"FIX","url":"https://github.com/modelcontextprotocol/typescript-sdk/pull/2925"},{"type":"PACKAGE","url":"https://github.com/modelcontextprotocol/typescript-sdk"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-10-24T02:50:10.551479324Z"}}