Improper Neutralization of Special Elements Used in a Template Engine in Mautic - CVE-2026-9558
Published: June 2, 2026
Vulnerability identifier: #VU133232
CSH Severity: Medium
CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-9558
CWE-ID: CWE-1336
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to compromise the target system.
The vulnerability exists due to server-side template injection (SSTI) issue in Theme Templates. A remote user can execute arbitrary code on the system.
Affected software
Mautic
How to mitigate CVE-2026-9558
Install updates from vendor's website.
Mautic - addressed in versions 4.4.20, 5.2.11, 6.0.9, 7.1.2