CVE-2025-54001: Themerex Classter

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

Deserialization of Untrusted Data vulnerability in ThemeREX Classter classter allows Object Injection.This issue affects Classter: from n/a through <= 2.5.

Affected products

• Themerex Classter: up to and including 2.5

Published 2026-03-05. Last modified 2026-06-17.