{"id":"CVE-2026-86730","summary":"Craft CMS 5.0.0-RC1 before 5.10.12 Behavior Injection RCE","details":"Craft CMS versions before 5.10.12 fail to properly cleanse string-typed field-layout elements, allowing authenticated control-panel users to inject Yii2 behavior attachments and event handlers. Attackers can post field-layout tab elements as JSON strings to bypass cleanse validation, then trigger arbitrary object instantiation and code execution through Craft::createObject().","aliases":["GHSA-qj4v-m29p-fj4m"],"modified":"2026-09-10T03:48:32.079177877Z","published":"2026-09-08T15:14:00.853Z","database_specific":{"cna_assigner":"VulnCheck","cwe_ids":["CWE-94"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/86xxx/CVE-2026-86730.json"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/86xxx/CVE-2026-86730.json"},{"type":"ADVISORY","url":"https://github.com/craftcms/cms/security/advisories/GHSA-qj4v-m29p-fj4m"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-86730"},{"type":"ADVISORY","url":"https://www.vulncheck.com/advisories/craft-cms-5.0.0-rc1-before-5.10.12-behavior-injection-rce"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/craftcms/cms","events":[{"introduced":"04755d93f86d07cc183db47db8a0eee106892e30"},{"fixed":"4edc686e69515ad42f5608580e351c765b664f80"}],"database_specific":{"source":["AFFECTED_FIELD","DESCRIPTION"],"extracted_events":[{"introduced":"5.0.0-RC1"},{"fixed":"5.10.12"},{"introduced":"0"}]}}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-86730.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:H/VI:H/VA:H/SC:N/SI:N/SA:N"}]}