CVE-2026-77136: TYPO3 Extension Powermail

Critical severity, CVSS 9.5. EPSS: 1% chance of exploitation in the next 30 days.

The extension passes the raw value of a form field configured as "This field contains the name of the sender" directly into a Fluid View as template source, without any sanitization, and renders it. An anonymous, unauthenticated user can submit Fluid template syntax in that field to execute arbitrary Fluid ViewHelpers leading to disclosure of server configuration, environment variables and application source, and potentially remote code execution. Exploitation requires only that a form field is configured as the sender_name field, a common and default-adjacent Powermail configuration. No authentication or user interaction beyond a normal form submission is required. This vulnerability is reported to be actively exploited in the wild.

Affected products

• TYPO3 Extension Powermail: from 13.0.0, before 13.2.1 (fixed in 13.2.1); from 11.0.0, before 12.6.1 (fixed in 12.6.1); before 10.9.3 (fixed in 10.9.3)

Published 2026-08-25. Last modified 2026-09-28.