{"id":"CVE-2026-79537","title":"metatool-ai MetaMCP through 2.4.22 contains an insecure direct object reference (IDOR) in the MCP transport session dispatch","summary":"metatool-ai MetaMCP through 2.4.22 contains an insecure direct object reference (IDOR) in the MCP transport session dispatch. The session store (getSession in session-lifetime-manager.ts) is keyed only by the client-supplied mcp-session-…","severity":"none","published":"2026-09-29","updated":"2026-09-29","sourceUpdated":"2026-09-29T20:17:27.383","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-79537","references":[{"url":"https://github.com/metatool-ai/metamcp","label":"cve@mitre.org"},{"url":"https://www.traceforce.ai/security-advisories/cve-2026-79537","label":"cve@mitre.org"}],"tags":["nvd","cve.org"],"ingestedAt":"2026-09-29T19:44:04.162Z","slug":"CVE-2026-79537","body":"## Overview\n\nmetatool-ai MetaMCP through 2.4.22 contains an insecure direct object reference (IDOR) in the MCP transport session dispatch. The session store (getSession in session-lifetime-manager.ts) is keyed only by the client-supplied mcp-session-id header with no owner, namespace, or endpoint binding, and the per-endpoint authorization middleware validates only the URL endpoint's owner, never the session. An attacker who supplies another tenant's session id \" obtained without authentication from GET /metamcp/health/sessions, which discloses active session IDs and namespace UUIDs \" can list and execute the victim tenant's private MCP tools and exfiltrate their data using the victim's forwarded credentials.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}