CVE-2026-63001

REDAXO is a PHP-based content management system. Prior to 5.21.2, the mediaIsInUse() handler in redaxo/src/addons/media_manager/lib/media_manager.php inserts a Media Manager type name into raw backend warning HTML without escaping it when invoked through MEDIA_IS_IN_USE. An administrator with Media Manager access can store HTML in a type name, and the payload executes in another administrator's browser when that administrator tries to delete media referenced by the type's effects, enabling session theft or unauthorized backend actions. This issue is fixed in version 5.21.2.

  • Published Sep 23, 2026
  • CVSS 4.8 medium
  • 0.2% chance of exploitation in the next 30 days (EPSS)
  • A fix is available

Affected software

CVE-2026-63001 at the National Vulnerability Database