{"id":"CVE-2026-45781","revision":"dc6e1322eb004a928808a97d5efa68a7","records":[{"revision":"dc6e1322eb004a928808a97d5efa68a7","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-45781","aliases":[],"title":"MCP Registry: OCI ownership validation fails open on upstream rate limits, allowing attacker-controlled package claims","description":"The MCP Registry provides MCP clients with a list of MCP servers, like an app store for MCP servers. Prior to 1.7.9, OCI ownership validation skips label-match check when upstream OCI registry returns HTTP 429, letting any authenticated publisher bind their io.github.<user>/* namespace to OCI images they do not control. internal/validators/registries/oci.go:104-119 fails open on http.StatusTooManyRequests: when the registry's anonymous fetch to the upstream OCI registry is rate-limited, ValidateOCI returns nil and the publish is accepted without ever running the io.modelcontextprotocol.server.name label-match check at lines 122-141. That label check is the only cross-system ownership proof the registry applies to OCI packages — every other registry type (NPM, PyPI, NuGet, MCPB) treats a non-200 upstream response as a hard error. This vulnerability is fixed in 1.7.9.","state":0,"publishedAt":"2026-05-14T21:00:49.961+00:00","modifiedAt":"2026-05-16T01:06:38.302+00:00","affected":[{"ecosystem":"Vendor product","name":"registry","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"modelcontextprotocol\",\n                    \"product\": \"registry\",\n                    \"versions\": [\n                        {\n                            \"version\": \"< 1.7.9\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N","score":3.5,"severity":"LOW"}],"references":["https://github.com/modelcontextprotocol/registry/security/advisories/GHSA-2v5f-5r6w-p67r"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-45781","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-45781","identifiers":["CVE-2026-45781"]},"retained":false,"historicalAffected":[]}],"coverage":[]}