{"id":"CVE-2026-53509","revision":"0cd68bbdbc884e519b12a54f4449cc22","records":[{"revision":"0cd68bbdbc884e519b12a54f4449cc22","observedAt":"2026-10-25T13:17:16.273+00:00","statement":{"source":"nvd","id":"CVE-2026-53509","aliases":[],"title":"CKAN MCP Server is a tool for querying CKAN open data portals. A known vulnerability CVE-2026-33060 indicated tools including ckan_package_search and sparql_query that accept a base_url parameter had the risk of making HTTP requests to arbi…","description":"CKAN MCP Server is a tool for querying CKAN open data portals. A known vulnerability CVE-2026-33060 indicated tools including ckan_package_search and sparql_query that accept a base_url parameter had the risk of making HTTP requests to arbitrary endpoints without restriction. A fix was applied to filter out ip addresses. However, a method to bypass exists prior to version 0.4.106. CKAN MCP Server validates caller-supplied CKAN server URLs by inspecting only the parsed hostname string before issuing outbound HTTP requests. In `src/utils/http.ts`, hostname aliases such as `ip6-localhost` are not equal to `localhost`, are not dotted IPv4 literals, and are not bracketed IPv6 literals, so they pass the SSRF filter but can resolve to loopback when the server performs the request. A remote MCP caller that can invoke CKAN tools with a `server_url` can therefore make the server connect to local or private addresses and, for CKAN-shaped responses, receive response-derived data. The updated fix in version 0.4.106 replaced the single `hostname === 'localhost'` check with a blocked-hostname `Set` covering `ip6-localhost` and `ip6-loopback`.","state":0,"publishedAt":"2026-08-21T22:16:38.993+00:00","modifiedAt":"2026-10-12T16:10:00.22+00:00","affected":[],"metrics":[{"system":"CVSS 3.1 · security-advisories@github.com · Secondary","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N","score":5.7,"severity":"MEDIUM"}],"references":["https://github.com/advisories/GHSA-3xm7-qw7j-qc8v","https://github.com/ondata/ckan-mcp-server/releases/tag/v0.4.106","https://github.com/ondata/ckan-mcp-server/security/advisories/GHSA-g84h-j7jj-x32p"],"sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-53509","license":"NIST NVD usage terms; underlying source attribution retained","enrichment":{"sourceStatus":"Deferred","weaknesses":["CWE-918"],"productCriteria":[],"sourceDates":{"published":"2026-08-21T22:16:38.993","lastModified":"2026-10-12T16:10:00.220"},"relatedAdvisories":[],"note":"NVD analysis and CPE criteria are source context, not proof that a package or your environment is affected. Complete affected data, logical configurations and SSVC are retained in the original JSON."},"key":"nvd:CVE-2026-53509","identifiers":["CVE-2026-53509"]},"retained":false,"historicalAffected":[]}],"coverage":[]}