{"id":"CVE-2026-77321","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-77321","generatedAt":"2026-10-28T01:45:23.667Z","title":"Cross-user trip authorization remains enforced, but the missing scope check defeats the consented least-privilege boundary and exposes trip content and third-party contact information to an MCP client that was not authorized to read it.","description":"TREK is a collaborative travel planner. Prior to 3.3.0, the get_trip_summary tool in server/src/mcp/tools/trips.ts is registered for scoped OAuth MCP tokens without requiring trips:read and returns core trip summary data regardless of the delegated scopes. A token granted only an unrelated capability, such as weather:read, can receive trip metadata, member email addresses from server/src/services/tripService.ts, itinerary days, and accommodations for every trip accessible to the token's user. Cross-user trip authorization remains enforced, but the missing scope check defeats the consented least-privilege boundary and exposes trip content and third-party contact information to an MCP client that was not authorized to read it. This issue is fixed in version 3.3.0.","published":"2026-09-24T19:17:17.000Z","lastModified":"2026-10-05T16:17:16.000Z","status":"Deferred","sourceIdentifier":"security-advisories@github.com","cvss":{"version":"3.1","score":4.3,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N"},"cwe":["CWE-200","CWE-284","CWE-862"],"affected":[],"epss":{"score":0.00199,"percentile":0.09661,"date":"2026-10-26","history":[{"date":"2026-09-25","score":0.00199,"percentile":0.08712}]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (0.20%). Track it; it rarely justifies an emergency change on its own."},"changes":[{"kind":"new","label":"New CVE","at":"2026-09-24T19:17:17.000Z","detail":{"score":"4.3","severity":"MEDIUM","publishedAt":"2026-09-24T19:17:16.887Z"},"summary":"New CVE, medium severity (CVSS 4.3)."}],"references":[{"url":"https://github.com/liketrek/TREK/commit/19064b39176660f3be3a2df198c87949504046e2","source":"security-advisories@github.com"},{"url":"https://github.com/liketrek/TREK/pull/1520","source":"security-advisories@github.com"},{"url":"https://github.com/liketrek/TREK/releases/tag/v3.3.0","source":"security-advisories@github.com"},{"url":"https://github.com/liketrek/TREK/security/advisories/GHSA-qvw8-w937-vcmq","source":"security-advisories@github.com"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-77321","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}