{"cve":"CVE-2026-53509","nvd":{"published":"2026-08-21T22:16:38.993","modified":"2026-10-12T16:10:00.220","status":"Deferred","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`.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N","score":5.7},"cwes":["CWE-918"],"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"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:49:38.260478770+00:00"},"epss":{"cve":"CVE-2026-53509","score":0.00384,"percentile":0.32146,"date":"2026-10-25"},"kev":null,"osv":[{"id":"GHSA-g84h-j7jj-x32p","url":"https://osv.dev/vulnerability/GHSA-g84h-j7jj-x32p","summary":"@aborruso/ckan-mcp-server: SSRF via base_url allows access to internal networks (Potential fix bypass of CVE-2026-33060)","modified":"2026-09-23T03:56:42.740372978Z","packages":[{"ecosystem":"npm","name":"@aborruso/ckan-mcp-server","purl":"pkg:npm/%40aborruso/ckan-mcp-server","ranges":["<0.4.106"],"fixed":["0.4.106"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}