Remote Code Execution in extension "HTML5 Video Player vs. Powermail" (html5videoplayer_powermail)
The extension fails to safely process untrusted client input of an attacker-controlled cookie directly to PHP's unserialize(). A remote, unauthenticated attacker can supply a crafted serialized payload to trigger PHP Object Injection, leading to Remote Code Execution on the TYPO3 server.
Severity critical: primary CNA CVSS 9.3 v4.0 (worst CNA-provided scenario) Not listed in this KEV snapshot. Forecast present in this snapshot.
Published 2026-08-25T09:00:38.059Z. Updated 2026-08-25T14:05:40.648Z.