{"affected":[{"product":"typescript-sdk","source":"CNA: GitHub_M","vendor":"modelcontextprotocol","versions":[{"status":"affected","version":">= 1.6.0, < 1.32.0"}]},{"product":"sdk","source":"CNA: GitHub_M","vendor":"@modelcontextprotocol","versions":[{"status":"affected","version":">= 1.6.0, < 1.32.0"}]},{"product":"server","source":"CNA: GitHub_M","vendor":"@modelcontextprotocol","versions":[{"status":"affected","version":">= 2.0.0, < 2.3.0"}]},{"product":"express","source":"CNA: GitHub_M","vendor":"@modelcontextprotocol","versions":[{"status":"affected","version":">= 2.0.0, < 2.0.2"}]},{"product":"server-legacy","source":"CNA: GitHub_M","vendor":"@modelcontextprotocol","versions":[{"status":"affected","version":">= 2.0.0, < 2.3.1"}]},{"ecosystem":"npm","packageName":"@modelcontextprotocol/sdk","product":"@modelcontextprotocol/sdk","source":"GitHub GHSA-rvq5-wwqv-78pq","vendor":"","versions":[{"status":"affected","version":">= 1.6.0, < 1.32.0","versionType":"GitHub advisory range"}]},{"ecosystem":"npm","packageName":"@modelcontextprotocol/server","product":"@modelcontextprotocol/server","source":"GitHub GHSA-rvq5-wwqv-78pq","vendor":"","versions":[{"status":"affected","version":">= 2.0.0, < 2.3.0","versionType":"GitHub advisory range"}]},{"ecosystem":"npm","packageName":"@modelcontextprotocol/express","product":"@modelcontextprotocol/express","source":"GitHub GHSA-rvq5-wwqv-78pq","vendor":"","versions":[{"status":"affected","version":">= 2.0.0, < 2.0.2","versionType":"GitHub advisory range"}]},{"ecosystem":"npm","packageName":"@modelcontextprotocol/server-legacy","product":"@modelcontextprotocol/server-legacy","source":"GitHub GHSA-rvq5-wwqv-78pq","vendor":"","versions":[{"status":"affected","version":">= 2.0.0, < 2.3.1","versionType":"GitHub advisory range"}]},{"defaultStatus":"unaffected","ecosystem":"npm","packageName":"@modelcontextprotocol/sdk","product":"@modelcontextprotocol/sdk","source":"OSV GHSA-rvq5-wwqv-78pq","vendor":"","versions":[{"events":[{"introduced":"1.6.0"},{"fixed":"1.32.0"}],"lessThan":"1.32.0","status":"affected","version":"1.6.0","versionType":"semver"}]},{"defaultStatus":"unaffected","ecosystem":"npm","packageName":"@modelcontextprotocol/server","product":"@modelcontextprotocol/server","source":"OSV GHSA-rvq5-wwqv-78pq","vendor":"","versions":[{"events":[{"introduced":"2.0.0"},{"fixed":"2.3.0"}],"lessThan":"2.3.0","status":"affected","version":"2.0.0","versionType":"semver"}]},{"defaultStatus":"unaffected","ecosystem":"npm","packageName":"@modelcontextprotocol/express","product":"@modelcontextprotocol/express","source":"OSV GHSA-rvq5-wwqv-78pq","vendor":"","versions":[{"events":[{"introduced":"2.0.0"},{"fixed":"2.0.2"}],"lessThan":"2.0.2","status":"affected","version":"2.0.0","versionType":"semver"}]},{"defaultStatus":"unaffected","ecosystem":"npm","packageName":"@modelcontextprotocol/server-legacy","product":"@modelcontextprotocol/server-legacy","source":"OSV GHSA-rvq5-wwqv-78pq","vendor":"","versions":[{"events":[{"introduced":"2.0.0"},{"fixed":"2.3.1"}],"lessThan":"2.3.1","status":"affected","version":"2.0.0","versionType":"semver"}]}],"cveId":"CVE-2026-111771","cwes":["CWE-863"],"description":"The Model Context Protocol TypeScript SDK provides TypeScript client and server implementations of the Model Context Protocol. From 1.6.0 until 1.32.0 in @modelcontextprotocol/sdk, from 2.0.0 until 2.3.0 in @modelcontextprotocol/server, from 2.0.0 until 2.0.2 in @modelcontextprotocol/express, and from 2.0.0 until 2.3.1 in @modelcontextprotocol/server-legacy, server-side bearer authentication could accept a valid access token issued for a different service because the SDK did not enforce the token audience. The affected surface is server-side HTTP bearer authentication. The trigger is a valid token whose audience names another service. The authorization server must issue tokens for multiple services, and the application's verifyAccessToken() must not independently validate aud. Applications already validating aud inside verifyAccessToken() are not affected. An attacker with a token for another service could authenticate to the MCP server and obtain the confidentiality and integrity capabilities granted to an authenticated caller. Upgrading alone leaves the new audience validation disabled. Operators must enable audience validation and provide the token audience together. Enabling only the expected audience check causes every request to receive HTTP 401. This issue is fixed in @modelcontextprotocol/sdk 1.32.0, @modelcontextprotocol/server 2.3.0, @modelcontextprotocol/express 2.0.2, and @modelcontextprotocol/server-legacy 2.3.1.","epss":{"date":"2026-11-09","percentile":0.45792,"score":0.00541},"exploits":[],"kev":null,"metrics":[{"score":6.8,"severity":"medium","source":"CNA: GitHub_M","vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N","version":"3.1"},{"score":6.8,"severity":"medium","source":"NVD: security-advisories@github.com","vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N","version":"3.1"}],"modifiedAt":1794287862073,"publishedAt":1793912935758,"references":[{"source":"CNA: GitHub_M","tags":["x_refsource_CONFIRM"],"url":"https://github.com/modelcontextprotocol/typescript-sdk/security/advisories/GHSA-rvq5-wwqv-78pq"},{"source":"CNA: GitHub_M","tags":["x_refsource_MISC"],"url":"https://github.com/modelcontextprotocol/typescript-sdk/pull/2929"},{"source":"CNA: GitHub_M","tags":["x_refsource_MISC"],"url":"https://github.com/modelcontextprotocol/typescript-sdk/pull/2930"},{"source":"CNA: GitHub_M","tags":["x_refsource_MISC"],"url":"https://github.com/modelcontextprotocol/typescript-sdk/pull/2952"},{"source":"CNA: GitHub_M","tags":["x_refsource_MISC"],"url":"https://github.com/modelcontextprotocol/typescript-sdk/commit/40f8f4e229d963cd7fd2890bda2aeebe7005299a"},{"source":"CNA: GitHub_M","tags":["x_refsource_MISC"],"url":"https://github.com/modelcontextprotocol/typescript-sdk/commit/5a0724d14cf34a27a3b070224d2996cdd611df9f"},{"source":"CNA: GitHub_M","tags":["x_refsource_MISC"],"url":"https://github.com/modelcontextprotocol/typescript-sdk/commit/5a1867390b91b8836f49af76c45427279f513325"},{"source":"CNA: GitHub_M","tags":["x_refsource_MISC"],"url":"https://github.com/modelcontextprotocol/typescript-sdk/releases/tag/1.32.0"},{"source":"CNA: GitHub_M","tags":["x_refsource_MISC"],"url":"https://github.com/modelcontextprotocol/typescript-sdk/releases/tag/@modelcontextprotocol/express@2.0.2"},{"source":"CNA: GitHub_M","tags":["x_refsource_MISC"],"url":"https://github.com/modelcontextprotocol/typescript-sdk/releases/tag/@modelcontextprotocol/server-legacy@2.3.1"},{"source":"CNA: GitHub_M","tags":["x_refsource_MISC"],"url":"https://github.com/modelcontextprotocol/typescript-sdk/releases/tag/@modelcontextprotocol/server@2.3.0"},{"source":"security-advisories@github.com","tags":[],"url":"https://github.com/modelcontextprotocol/typescript-sdk/commit/40f8f4e229d963cd7fd2890bda2aeebe7005299a"},{"source":"security-advisories@github.com","tags":[],"url":"https://github.com/modelcontextprotocol/typescript-sdk/commit/5a0724d14cf34a27a3b070224d2996cdd611df9f"},{"source":"security-advisories@github.com","tags":[],"url":"https://github.com/modelcontextprotocol/typescript-sdk/commit/5a1867390b91b8836f49af76c45427279f513325"},{"source":"security-advisories@github.com","tags":[],"url":"https://github.com/modelcontextprotocol/typescript-sdk/pull/2929"},{"source":"security-advisories@github.com","tags":[],"url":"https://github.com/modelcontextprotocol/typescript-sdk/pull/2930"},{"source":"security-advisories@github.com","tags":[],"url":"https://github.com/modelcontextprotocol/typescript-sdk/pull/2952"},{"source":"security-advisories@github.com","tags":[],"url":"https://github.com/modelcontextprotocol/typescript-sdk/releases/tag/1.32.0"},{"source":"security-advisories@github.com","tags":[],"url":"https://github.com/modelcontextprotocol/typescript-sdk/releases/tag/@modelcontextprotocol/express@2.0.2"},{"source":"security-advisories@github.com","tags":[],"url":"https://github.com/modelcontextprotocol/typescript-sdk/releases/tag/@modelcontextprotocol/server-legacy@2.3.1"},{"source":"security-advisories@github.com","tags":[],"url":"https://github.com/modelcontextprotocol/typescript-sdk/releases/tag/@modelcontextprotocol/server@2.3.0"},{"source":"security-advisories@github.com","tags":[],"url":"https://github.com/modelcontextprotocol/typescript-sdk/security/advisories/GHSA-rvq5-wwqv-78pq"},{"source":"GitHub Security Advisories","tags":["advisory"],"url":"https://github.com/modelcontextprotocol/typescript-sdk/security/advisories/GHSA-rvq5-wwqv-78pq"},{"source":"OSV / GitHub Security Advisories","tags":["advisory"],"url":"https://github.com/advisories/GHSA-rvq5-wwqv-78pq"},{"source":"OSV / GitHub Security Advisories","tags":["osv"],"url":"https://osv.dev/vulnerability/GHSA-rvq5-wwqv-78pq"}],"remediation":[{"kind":"fix","source":"GitHub GHSA-rvq5-wwqv-78pq","text":"@modelcontextprotocol/sdk (npm): GitHub reports patched versions 1.32.0. Check the advisory for the affected release branch.","url":"https://github.com/modelcontextprotocol/typescript-sdk/security/advisories/GHSA-rvq5-wwqv-78pq"},{"kind":"fix","source":"GitHub GHSA-rvq5-wwqv-78pq","text":"@modelcontextprotocol/server (npm): GitHub reports patched versions 2.3.0. Check the advisory for the affected release branch.","url":"https://github.com/modelcontextprotocol/typescript-sdk/security/advisories/GHSA-rvq5-wwqv-78pq"},{"kind":"fix","source":"GitHub GHSA-rvq5-wwqv-78pq","text":"@modelcontextprotocol/express (npm): GitHub reports patched versions 2.0.2. Check the advisory for the affected release branch.","url":"https://github.com/modelcontextprotocol/typescript-sdk/security/advisories/GHSA-rvq5-wwqv-78pq"},{"kind":"fix","source":"GitHub GHSA-rvq5-wwqv-78pq","text":"@modelcontextprotocol/server-legacy (npm): GitHub reports patched versions 2.3.1. Check the advisory for the affected release branch.","url":"https://github.com/modelcontextprotocol/typescript-sdk/security/advisories/GHSA-rvq5-wwqv-78pq"},{"kind":"fix","source":"OSV GHSA-rvq5-wwqv-78pq","text":"@modelcontextprotocol/sdk (npm): OSV reports a fixed version 1.32.0. Check the advisory for supported release branches.","url":"https://github.com/advisories/GHSA-rvq5-wwqv-78pq"},{"kind":"fix","source":"OSV GHSA-rvq5-wwqv-78pq","text":"@modelcontextprotocol/server (npm): OSV reports a fixed version 2.3.0. Check the advisory for supported release branches.","url":"https://github.com/advisories/GHSA-rvq5-wwqv-78pq"},{"kind":"fix","source":"OSV GHSA-rvq5-wwqv-78pq","text":"@modelcontextprotocol/express (npm): OSV reports a fixed version 2.0.2. Check the advisory for supported release branches.","url":"https://github.com/advisories/GHSA-rvq5-wwqv-78pq"},{"kind":"fix","source":"OSV GHSA-rvq5-wwqv-78pq","text":"@modelcontextprotocol/server-legacy (npm): OSV reports a fixed version 2.3.1. Check the advisory for supported release branches.","url":"https://github.com/advisories/GHSA-rvq5-wwqv-78pq"}],"revision":"89b5429f468a57452fb0a1b8cb95abecf2c5dcac1bd3988ded7bdb4d91560c41","sources":[{"modifiedAt":1794284481841,"name":"CNA: GitHub_M","retrievedAt":1794287309023,"url":"https://www.cve.org/CVERecord?id=CVE-2026-111771"},{"modifiedAt":1794287862073,"name":"NVD","retrievedAt":1794291346446,"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-111771"},{"modifiedAt":1792440727000,"name":"GitHub Security Advisories","retrievedAt":1794093909465,"url":"https://github.com/modelcontextprotocol/typescript-sdk/security/advisories/GHSA-rvq5-wwqv-78pq"},{"modifiedAt":1792526404595,"name":"OSV / GitHub Security Advisories","retrievedAt":1793916773817,"url":"https://osv.dev/vulnerability/GHSA-rvq5-wwqv-78pq"},{"modifiedAt":null,"name":"FIRST EPSS","retrievedAt":1794287329273,"url":"https://api.first.org/data/v1/epss?cve=CVE-2026-111771"}],"ssvc":{"assessedAt":1794284460140,"automatable":"no","exploitation":"none","source":"ADP: CISA-ADP","technicalImpact":"total"},"status":"published","title":"Model Context Protocol TypeScript SDK: Server bearer authentication accepted tokens issued for another service","updatedAt":1794291346446}