Formidable Forms <= 6.0.1 - IP Spoofing via HTTP header

Reliance on Untrusted Inputs in a Security Decision
CVE CVE-2023-0816
CVSS Medium (5.3)
Publicly Published March 6, 2023
Last Updated January 22, 2024
Researcher Daniel Ruf
Description

The Formidable Forms plugin for WordPress is vulnerable to IP Spoofing in versions up to, and including, 6.0.1 due to a reliance on various untrusted headers (e.g., 'Client-Ip', 'CF-CONNECTING-IP', etc.) to retrieve the IP address of a client performing a form submission. This makes it possible for unauthenticated users to bypass the plugin's anti-spam protections.

References

1 affected software package

Software Type Plugin
Software Slug formidable (view on wordpress.org)
Patched? Yes
Affected Version
  • <= 6.0.1
Patched Version
  • 6.1
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