CVE-2026-77136 Server-Side Template Injection in extension "powermail" (powermail)
Unauthenticated attackers can inject Fluid template syntax into sender name fields to execute code and read sensitive data in TYPO3 powermail.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-77136?
CVE-2026-77136 is a critical code injection vulnerability in TYPO3 Extension "powermail", published on 25 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
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.
Weakness: CWE-1336
Which versions are affected by CVE-2026-77136?
How do I fix CVE-2026-77136?
No fix has been published for CVE-2026-77136 yet. Limit exposure of the affected software until one is available.
Upgrade, and never evaluate templates, expressions or code built from user input. More about Code injection.
Is CVE-2026-77136 being exploited?
There is no known exploitation of CVE-2026-77136 in the wild and no public exploit code.
Sources
Also known as GHSA-6956-f2gq-2c74.