{"id":"CVE-2026-27129","state":"PUBLISHED","title":"Cloud Metadata SSRF Protection Bypass via IPv6 Resolution","description":"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 `<VolumeName>` volume and creating assets in the `<VolumeName>` 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.","publishedAt":"2026-02-24T02:45:45.494Z","updatedAt":"2026-02-28T02:17:18.957Z","severity":{"score":5.7,"label":"Medium","version":"4.0","vector":"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","source":"GitHub_M"},"assigner":"GitHub_M","products":["craftcms cms"],"affected":[{"vendor":"craftcms","product":"cms","versions":[{"version":">= 4.5.0-RC1, < 4.16.19","status":"affected"},{"version":">= 5.0.0-RC1, < 5.8.23","status":"affected"}]}],"references":["https://github.com/craftcms/cms/security/advisories/GHSA-v2gc-rm6g-wrw9","https://github.com/craftcms/cms/security/advisories/GHSA-x27p-wfqw-hfcc","https://github.com/craftcms/cms/commit/2825388b4f32fb1c9bd709027a1a1fd192d709a3"],"weaknesses":["CWE-918"],"ingestedAt":"2026-10-29T20:11:31.369Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/27xxx/CVE-2026-27129.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-27129","state":"PUBLISHED","datePublished":"2026-02-24T02:45:45.494Z","dateUpdated":"2026-02-28T02:17:18.957Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-02-17T18:42:27.043Z"},"containers":{"cna":{"title":"Cloud Metadata SSRF Protection Bypass via IPv6 Resolution","descriptions":[{"lang":"en","value":"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 `<VolumeName>` volume and creating assets in the `<VolumeName>` 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."}],"affected":[{"vendor":"craftcms","product":"cms","versions":[{"version":">= 4.5.0-RC1, < 4.16.19","status":"affected"},{"version":">= 5.0.0-RC1, < 5.8.23","status":"affected"}]}],"references":[{"url":"https://github.com/craftcms/cms/security/advisories/GHSA-v2gc-rm6g-wrw9","name":"https://github.com/craftcms/cms/security/advisories/GHSA-v2gc-rm6g-wrw9","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/craftcms/cms/security/advisories/GHSA-x27p-wfqw-hfcc","name":"https://github.com/craftcms/cms/security/advisories/GHSA-x27p-wfqw-hfcc","tags":["x_refsource_MISC"]},{"url":"https://github.com/craftcms/cms/commit/2825388b4f32fb1c9bd709027a1a1fd192d709a3","name":"https://github.com/craftcms/cms/commit/2825388b4f32fb1c9bd709027a1a1fd192d709a3","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV4_0":{"attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"LOW","userInteraction":"NONE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"HIGH","vulnAvailabilityImpact":"NONE","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","baseScore":5.7,"baseSeverity":"MEDIUM","vectorString":"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","version":"4.0"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-918","lang":"en","description":"CWE-918: Server-Side Request Forgery (SSRF)","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-02-24T02:45:45.494Z"},"source":{"advisory":"GHSA-v2gc-rm6g-wrw9","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-02-28T02:16:52.966432Z","id":"CVE-2026-27129","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-02-28T02:17:18.957Z"}}]}}}