SB2026082628 - Server-Side Template Injection (SSTI) in powermail extension for TYPO3
Published: August 26, 2026
Security Bulletin ID
SB2026082628
CSH Severity
High
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Remote access
Highest impact
Code execution
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Improper Neutralization of Special Elements Used in a Template Engine (CVE-ID: CVE-2026-77136)
CWE-ID: CWE-1336 - Improper Neutralization of Special Elements Used in a Template Engine
CVSSv4: 9.2 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a remote attacker to compromise the target system.
The vulnerability exists due to improper neutralization of special elements used in a template engine. A remote user can submit Fluid template syntax to execute arbitrary Fluid ViewHelpers and disclose the server configuration, leading to arbitrary code execution.
Remediation
Install update from vendor's website.