{"id":"CVE-2026-55998","aliases":["EUVD-2026-53258","GHSA-23h9-rr79-r3gh"],"status":"published","title":"Cluster Existence Oracle via Unauthenticated Import Endpoint","description":"The endpoint /v3/import/{token}_{clusterId}.yaml retrieves the cluster object before validating the token. When a valid cluster ID references a cluster that has private registry secrets configured, a nil pointer dereference in pkg/systemtemplate/private_registry.go causes the request to return HTTP 502 Bad Gateway. For cluster IDs that do not exist, the endpoint returns HTTP 200. This observable difference in response codes constitutes a reliable enumeration oracle.","severity":{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.00343,"percentile":0.28172,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-204"],"published":"2026-08-05T07:51:21Z","modified":"2026-10-28T02:30:53Z","products":[{"vendor":"suse","product":"rancher"}],"references":[{"url":"https://github.com/rancher/rancher/security/advisories/GHSA-23h9-rr79-r3gh","tags":["advisory"]},{"url":"https://bugzilla.suse.com/show_bug.cgi?id=CVE-2026-55998","tags":["report"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/55xxx/CVE-2026-55998.json","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-55998","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-55998","title":"Cluster Existence Oracle via Unauthenticated Import Endpoint","description":"The endpoint /v3/import/{token}_{clusterId}.yaml retrieves the cluster object before validating the token. When a valid cluster ID references a cluster that has private registry secrets configured, a nil pointer dereference in pkg/systemtemplate/private_registry.go causes the request to return HTTP 502 Bad Gateway. For cluster IDs that do not exist, the endpoint returns HTTP 200. This observable difference in response codes constitutes a reliable enumeration oracle.","status":"published","published":"2026-08-05T07:51:21.731Z","modified":"2026-08-05T13:13:02.031Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium","assessor":"cna"}],"cwes":["CWE-204"],"updated_at":"2026-11-02T14:20:11.925815Z"}],"euvd":[{"id":"EUVD-2026-53258","description":"The endpoint /v3/import/{token}_{clusterId}.yaml retrieves the cluster object before validating the token. When a valid cluster ID references a cluster that has private registry secrets configured, a nil pointer dereference in pkg/systemtemplate/private_registry.go causes the request to return HTTP 502 Bad Gateway. For cluster IDs that do not exist, the endpoint returns HTTP 200. This observable difference in response codes constitutes a reliable enumeration oracle.","status":"published","published":"2026-08-05T07:51:21Z","modified":"2026-08-05T13:13:02Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium"}],"updated_at":"2026-11-02T18:02:10.813132Z"}],"nvd":[{"id":"CVE-2026-55998","description":"The endpoint /v3/import/{token}_{clusterId}.yaml retrieves the cluster object before validating the token. When a valid cluster ID references a cluster that has private registry secrets configured, a nil pointer dereference in pkg/systemtemplate/private_registry.go causes the request to return HTTP 502 Bad Gateway. For cluster IDs that do not exist, the endpoint returns HTTP 200. This observable difference in response codes constitutes a reliable enumeration oracle.","status":"published","published":"2026-08-05T08:16:34.46Z","modified":"2026-10-24T16:10:00.153Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium","assessor":"secondary"}],"cwes":["CWE-204"],"updated_at":"2026-11-02T14:12:35.031043Z"}],"osv":[{"id":"CVE-2026-55998","title":"Cluster Existence Oracle via Unauthenticated Import Endpoint","description":"The endpoint /v3/import/{token}_{clusterId}.yaml retrieves the cluster object before validating the token. When a valid cluster ID references a cluster that has private registry secrets configured, a nil pointer dereference in pkg/systemtemplate/private_registry.go causes the request to return HTTP 502 Bad Gateway. For cluster IDs that do not exist, the endpoint returns HTTP 200. This observable difference in response codes constitutes a reliable enumeration oracle.","status":"published","published":"2026-08-05T07:51:21.731Z","modified":"2026-10-28T02:30:53.023385168Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium"}],"cwes":["CWE-204"],"updated_at":"2026-11-02T15:45:11.609219Z"}]}}