{"id":"CVE-2026-31857","summary":"CraftCMS has an RCE vulnerability via relational conditionals in the control panel","details":"Craft is a content management system (CMS). Prior to 5.9.9 and 4.17.4, a Remote Code Execution vulnerability exists in the Craft CMS 5 conditions system. The BaseElementSelectConditionRule::getElementIds() method passes user-controlled string input through renderObjectTemplate() -- an unsandboxed Twig rendering function with escaping disabled. Any authenticated Control Panel user (including non-admin roles such as Author or Editor) can achieve full RCE by sending a crafted condition rule via standard element listing endpoints. This vulnerability requires no admin privileges, no special permissions beyond basic control panel access, and bypasses all production hardening settings (allowAdminChanges: false, devMode: false, enableTwigSandbox: true). Users should update to the patched 5.9.9 or 4.17.4 release to mitigate the issue.","aliases":["GHSA-fp5j-j7j4-mcxc"],"modified":"2026-04-10T05:42:10.595384Z","published":"2026-03-11T17:30:29.092Z","database_specific":{"cna_assigner":"GitHub_M","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/31xxx/CVE-2026-31857.json","cwe_ids":["CWE-94"]},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/31xxx/CVE-2026-31857.json"},{"type":"ADVISORY","url":"https://github.com/craftcms/cms/security/advisories/GHSA-fp5j-j7j4-mcxc"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-31857"},{"type":"FIX","url":"https://github.com/craftcms/cms/commit/8d4903647dcfd31b8d40ed027e27082013347a80"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/craftcms/cms","events":[{"introduced":"04755d93f86d07cc183db47db8a0eee106892e30"},{"fixed":"74eb5d3a9ffa935df1a4fc2b6ddb1042d9f8e582"}],"database_specific":{"versions":[{"introduced":"5.0.0-RC1"},{"fixed":"5.9.9"}]}},{"type":"GIT","repo":"https://github.com/craftcms/cms","events":[{"introduced":"2c20eed81e34c35b880ddd9e1bc61c9cfd9c6690"},{"fixed":"5020fa5be830af712694f9f8164599a1789cc094"}],"database_specific":{"versions":[{"introduced":"4.0.0-beta.1"},{"fixed":"4.17.4"}]}}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-31857.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U"}]}