CVE-2026-54416
Pluck CMS through 4.7.21 restricts dangerous file uploads in its admin file-management feature using a fixed blacklist in data/inc/files.php ('.php','php3','php4','php5','php6','php7','phtml','.phtm','.pht','.ph3','.ph4','.ph5','.asp','.cgi','.phar'), checked against the last 4-5 characters of the filename. The blacklist omits the '.php8' extension. An authenticated administrator can upload a file named e.g. shell.php8, which is stored unmodified and, on servers running PHP 8.x, is executed as PHP by the web server, resulting in remote code execution.
No public exploitation has been reported so far. No distribution fix is listed yet; apply vendor mitigations and monitor.
Recommended action: Track your distribution's security tracker and apply the fix as soon as it ships.
Severity metrics
CVSS 3.1 : 7.2 HIGH
Vector: AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
Affected & fixed versions by distribution
Versions are the native distribution strings (backport-aware): RHEL/Debian/SUSE backport fixes, so compare with the distro version comparator (dpkg / rpm / vercmp), not the upstream version.
No affected package in the tracked watchlist yet (Debian, Ubuntu, Arch, SUSE, Red Hat...). Triage may still be pending.