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Security Alerts

CVE-2026-4257: Remote code execution in WordPress

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 d...

Summary

ParameterValue
CVE IDCVE-2026-4257
Alert SourceGitHub Advisory - Critical Vulnerability
CVE Publication Year2026
Date Published2026-03-31
VendorWordPress
ProductWordPress
CVSS Score9.8 (critical)
EPSS ScoreNo data
CISA KEVNo
RansomwareNot confirmed

Vulnerability Description

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 a…

Required Actions

Apply vendor patches or mitigations as soon as available.

Who Is Affected?

This vulnerability affects WordPress by WordPress. Check if your organization uses this software and requires updates.

Sources


Need help securing your systems? nFlo team offers vulnerability management and 24/7 SOC services. Contact us.

How can nFlo help?

If your organization uses products affected by this vulnerability, contact us. We can help with:

  • Verifying whether your systems are at risk
  • Implementing patches and risk mitigation
  • Monitoring for exploitation attempts in your environment

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