{"id":"CVE-2026-27129","summary":"Cloud Metadata SSRF Protection Bypass via IPv6 Resolution","details":"Craft is a content management system (CMS). In versions 4.5.0-RC1 through 4.16.18 and 5.0.0-RC1 through 5.8.22, the SSRF validation in Craft CMS’s GraphQL Asset mutation uses `gethostbyname()`, which only resolves IPv4 addresses. When a hostname has only AAAA (IPv6) records, the function returns the hostname string itself, causing the blocklist comparison to always fail and completely bypassing SSRF protection. This is a bypass of the security fix for CVE-2025-68437. Exploitation requires GraphQL schema permissions for editing assets in the `\u003cVolumeName\u003e` volume and creating assets in the `\u003cVolumeName\u003e` volume. These permissions may be granted to authenticated users with appropriate GraphQL schema access and/or Public Schema (if misconfigured with write permissions). Versions 4.16.19 and 5.8.23 patch the issue.","aliases":["GHSA-v2gc-rm6g-wrw9"],"modified":"2026-08-12T03:51:24.258900408Z","published":"2026-02-24T02:45:45.494Z","related":["GHSA-v2gc-rm6g-wrw9","GHSA-x27p-wfqw-hfcc"],"database_specific":{"cna_assigner":"GitHub_M","cwe_ids":["CWE-918"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/27xxx/CVE-2026-27129.json"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/27xxx/CVE-2026-27129.json"},{"type":"ADVISORY","url":"https://github.com/craftcms/cms/security/advisories/GHSA-v2gc-rm6g-wrw9"},{"type":"ADVISORY","url":"https://github.com/craftcms/cms/security/advisories/GHSA-x27p-wfqw-hfcc"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-27129"},{"type":"FIX","url":"https://github.com/craftcms/cms/commit/2825388b4f32fb1c9bd709027a1a1fd192d709a3"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/craftcms/cms","events":[{"introduced":"c6671af5af9e45f57ca9ab50d4b30b07282819d3"},{"fixed":"1a8db788c8b3de85c3aed09ac34046e230079481"},{"introduced":"856f45f2766b1a1df5db437b5cd3fe5cce896b5b"},{"fixed":"daf0ed01c7d2c194ba4a405290e43934d020eef2"},{"introduced":"f6a8fb685d44e387435825e3a96809eeda4973a6"},{"fixed":"2825388b4f32fb1c9bd709027a1a1fd192d709a3"}],"database_specific":{"cpe":["cpe:2.3:a:craftcms:craft_cms:*:*:*:*:*:*:*:*","cpe:2.3:a:craftcms:craft_cms:5.0.0:-:*:*:*:*:*:*","cpe:2.3:a:craftcms:craft_cms:5.0.0:rc1:*:*:*:*:*:*"],"extracted_events":[{"introduced":"3.5.0"},{"fixed":"4.16.19"},{"introduced":"5.0.1"},{"fixed":"5.8.23"},{"introduced":"5.0.0-NA"},{"last_affected":"5.0.0-NA"},{"introduced":"5.0.0-rc1"},{"last_affected":"5.0.0-rc1"}],"source":["CPE_RANGE","CPE_STRING","REFERENCES"]}}],"versions":["5.0.0-NA","5.0.0-rc1"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-27129.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:P"}]}