CVE-2025-54336

Critical severity, CVSS 9.8. EPSS: 0.5% chance of exploitation in the next 30 days.

In Plesk Obsidian 18.0.70, _isAdminPasswordValid uses an == comparison. Thus, if the correct password is "0e" followed by any digit string, then an attacker can login with any other string that evaluates to 0.0 (such as the 0e0 string). This occurs in admin/plib/LoginManager.php.

Published 2025-08-19. Last modified 2026-06-17.