CVE-2026-9558
Published:May 29, 2026
Updated:June 13, 2026
A Server-Side Template Injection (SSTI) vulnerability exists in Mautic's theme engine. The platform renders uploaded Twig templates without a sandbox or strict function restrictions. Authenticated users with permissions to create or upload themes can abuse this to execute arbitrary code on the hosting server (Remote Code Execution) or access restricted system files and configuration settings.
Affected Packages
https://github.com/mautic/mautic.git (GITHUB):
Affected version(s) >=5.0.0 <5.2.11Fix Suggestion:
Update to version 5.2.11https://github.com/mautic/mautic.git (GITHUB):
Affected version(s) >=7.0.0 <7.1.2Fix Suggestion:
Update to version 7.1.2https://github.com/mautic/mautic.git (GITHUB):
Affected version(s) >=6.0.0 <6.0.9Fix Suggestion:
Update to version 6.0.9mautic/core (PHP):
Affected version(s) >=6.0.0 <6.0.9Fix Suggestion:
Update to version 6.0.9mautic/core (PHP):
Affected version(s) >=5.0.0 <5.2.11Fix Suggestion:
Update to version 5.2.11mautic/core (PHP):
Affected version(s) >=7.0.0 <7.1.2Fix Suggestion:
Update to version 7.1.2Related Resources (1)
Do you need more information?
Contact UsCVSS v4
Base Score:
9.4
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
LOW
User Interaction
NONE
Vulnerable System Confidentiality
HIGH
Vulnerable System Integrity
HIGH
Vulnerable System Availability
HIGH
Subsequent System Confidentiality
HIGH
Subsequent System Integrity
HIGH
Subsequent System Availability
HIGH
CVSS v3
Base Score:
9.9
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
NONE
Scope
CHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH
Weakness Type (CWE)
Improper Neutralization of Special Elements Used in a Template Engine
EPSS
Base Score:
0.22