CVE-2025-54336

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.

Weakness

The product compares two entities in a security-relevant context, but the comparison is incorrect, which may lead to resultant weaknesses.

Extended Description

This Pillar covers several possibilities:

Related Attack Patterns

• https://cwe.mitre.org/data/definitions/10.html
• https://cwe.mitre.org/data/definitions/120.html
• https://cwe.mitre.org/data/definitions/14.html
• https://cwe.mitre.org/data/definitions/15.html
• https://cwe.mitre.org/data/definitions/182.html
• https://cwe.mitre.org/data/definitions/24.html
• https://cwe.mitre.org/data/definitions/267.html
• https://cwe.mitre.org/data/definitions/3.html
• https://cwe.mitre.org/data/definitions/41.html
• https://cwe.mitre.org/data/definitions/43.html
• https://cwe.mitre.org/data/definitions/44.html
• https://cwe.mitre.org/data/definitions/45.html
• https://cwe.mitre.org/data/definitions/46.html
• https://cwe.mitre.org/data/definitions/47.html
• https://cwe.mitre.org/data/definitions/52.html
• https://cwe.mitre.org/data/definitions/53.html
• https://cwe.mitre.org/data/definitions/6.html
• https://cwe.mitre.org/data/definitions/64.html
• https://cwe.mitre.org/data/definitions/67.html
• https://cwe.mitre.org/data/definitions/7.html
• https://cwe.mitre.org/data/definitions/71.html
• https://cwe.mitre.org/data/definitions/73.html
• https://cwe.mitre.org/data/definitions/78.html
• https://cwe.mitre.org/data/definitions/79.html
• https://cwe.mitre.org/data/definitions/8.html
• https://cwe.mitre.org/data/definitions/80.html
• https://cwe.mitre.org/data/definitions/88.html
• https://cwe.mitre.org/data/definitions/9.html
• https://cwe.mitre.org/data/definitions/92.html

References

• https://blog.aziz.tn/2025/08/cve-2025-54336.html/
• https://support.plesk.com/hc/en-us/articles/33785727869847-Vulnerability-CVE-2025-54336
• https://www.plesk.com/blog/plesk-news-announcements/introducing-plesk-obsidian-18-0-70-anniversary-edition/