Critical severity · published Aug 25, 2026
CVE-2026-77138
Remote Code Execution in extension "HTML5 Video Player vs. Powermail" (html5videoplayer_powermail)
9.3
CVSS
0.7%
EPSS
No
On KEV
Description
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.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.7% · higher than 54% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
EH
Extension "HTML5 Video Player vs. Powermail" · TYPO3
through 0.2.1 · source: vendor
Affected product
EH
Extension "HTML5 Video Player vs. Powermail"
TYPO3