CVE-2026-79537 (GCVE-0-2026-79537)

Vulnerability from cvelistv5 – Published: 2026-09-29 00:00 – Updated: 2026-09-29 19:17
VLAI
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-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.
Severity
No CVSS data available.
CWE
  • n/a
Assigner
References
Show details on NVD website
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    "datePublished": "2026-09-29T00:00:00.000Z",
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