Craft CMS vulnerable to potential authenticated Remote Code Execution via malicious attached Behavior
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 8.6epss 0.9%
exploitation probability
0.9%top 41% of all CVEs
observed exploitation
nono source reports it
Craft is a platform for creating digital experiences. Versions 5.0.0-RC1 through 5.8.20 and 4.0.0-RC1 through 4.16.16 are vulnerable to potential authenticated Remote Code Execution via malicious attached Behavior. Note that attackers must have administrator access to the Craft Control Panel for this to work. Users should update to the patched versions (5.8.21 and 4.16.17) to mitigate the issue.
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Affected products
craftcms · cmsReferences
https://github.com/craftcms/cms/blob/5.x/CHANGELOG.md#5821---2025-12-04https://github.com/craftcms/cms/commit/27f55886098b56c00ddc53b69239c9c9192252c7https://github.com/craftcms/cms/commit/6e608a1a5bfb36943f94f584b7548ca542a86fefhttps://github.com/craftcms/cms/commit/ec43c497edde0b2bf2e39a119cded2e55f9fe593https://github.com/craftcms/cms/security/advisories/GHSA-255j-qw47-wjh5