CVE-2026-4257
CRITICAL
9,8
Source: [email protected]
Attack Vector: network
Attack Complexity: low
Privileges Required: none
User Interaction: none
Scope: unchanged
Confidentiality: high
Integrity: high
Availability: high
Description
AI Translation Available
The Contact Form by Supsystic plugin for WordPress is vulnerable to Server-Side Template Injection (SSTI) leading to Remote Code Execution (RCE) in all versions up to, and including, 1.7.36. This is due to the plugin using the Twig `Twig_Loader_String` template engine without sandboxing, combined with the `cfsPreFill` prefill functionality that allows unauthenticated users to inject arbitrary Twig expressions into form field values via GET parameters. This makes it possible for unauthenticated attackers to execute arbitrary PHP functions and OS commands on the server by leveraging Twig's `registerUndefinedFilterCallback()` method to register arbitrary PHP callbacks.
94
Improper Control of Generation of Code ('Code Injection')
DraftCommon Consequences
Security Scopes Affected:
Access Control
Integrity
Confidentiality
Availability
Non-Repudiation
Potential Impacts:
Bypass Protection Mechanism
Gain Privileges Or Assume Identity
Execute Unauthorized Code Or Commands
Hide Activities
Applicable Platforms
Languages:
Interpreted
Technologies:
AI/ML
https://plugins.trac.wordpress.org/browser/contact-form-by-supsystic/tags/1.7.3…
https://plugins.trac.wordpress.org/changeset/3491826/contact-form-by-supsystic
https://www.wordfence.com/threat-intel/vulnerabilities/id/415c9658-bfb2-453b-a6…