MCP TypeScript SDK: Experimental tasks were not tied to the session that created them

{
  "id": "3db53986b71211939e52c9e10cbd91a697a8ef7f0f596edd352476adb2193a52",
  "url": "https://osv.dev/vulnerability/GHSA-22jm-h49p-29qw",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "MCP TypeScript SDK: Experimental tasks were not tied to the session that created them",
    "summary": "### Summary In 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. Experimental tasks are deprecated. The 2026-07-28 specification replaced them with a redesigned extension. The best course of action is to stop using them. ### Am I affected? Only if your HTTP server passes `taskStore` to `McpServer` or `Server`. If `grep -ri taskstore --exclude-dir=node_modules .` finds nothing, you are not affected. Affected versions: `@modelcontextprotocol/sdk` 1.24.0 through 1.31.0. The 2.x packages are not affected. ### Fix Upgrade 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. If you cannot upgrade yet, remove `taskStore`, or create one `InMemoryTaskStore` per session.",
    "evidence": "osv:GHSA-22jm-h49p-29qw",
    "products": [
      {
        "name": {
          "value": "@modelcontextprotocol/sdk",
          "evidence": "/affected/0/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "1.32.0",
            "evidence": "/affected/0/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "high",
    "structured": {
      "id": "GHSA-22jm-h49p-29qw",
      "aliases": [
        "CVE-2026-111767",
        "GHSA-22jm-h49p-29qw"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:L"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "type": "SEMVER",
              "events": [
                {
                  "introduced": "1.24.0"
                },
                {
                  "fixed": "1.32.0"
                }
              ]
            }
          ],
          "package": {
            "name": "@modelcontextprotocol/sdk",
            "purl": "pkg:npm/%40modelcontextprotocol/sdk",
            "ecosystem": "npm"
          },
          "database_specific": {
            "source": "https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/10/GHSA-22jm-h49p-29qw/GHSA-22jm-h49p-29qw.json"
          }
        }
      ],
      "modified": "2026-10-20T18:45:09.486849334Z",
      "provider": "osv",
      "references": [
        "https://github.com/modelcontextprotocol/typescript-sdk/security/advisories/GHSA-22jm-h49p-29qw",
        "https://github.com/modelcontextprotocol/typescript-sdk/pull/2925",
        "https://github.com/modelcontextprotocol/typescript-sdk/commit/727075b5bbeb77fbea22041b36b72a73042160fa",
        "https://github.com/modelcontextprotocol/typescript-sdk"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-639",
          "CWE-862"
        ],
        "severity": "HIGH",
        "github_reviewed": true,
        "nvd_published_at": null,
        "github_reviewed_at": "2026-10-20T18:26:54Z"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-111767",
        "evidence": "/aliases"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/database_specific/severity"
  },
  "source_id": "core-osv",
  "document_id": 390159,
  "published_at": "2026-10-20T18:26:54+00:00"
}