Medium · published September 21, 2026
CKAN MCP Server is a tool for querying CKAN open data portals. Prior to version 0.4.108, the SSRF guard `validateServerUrl` (added for CVE-2026-33060, extended for CVE-2026-53509) validates only the hostname string and never resolves DNS. Any caller-supplied `server_url` whose hostname *resolves* to an internal address passes the guard, so the server issues requests to loopback and cloud metadata (`169.254.169.254`). This is a third bypass of the same guard, and it reaches IMDS — strictly more than CVE-2026-53509, which only reached loopback. Version 0.4.108 contains an updated fix.