vulnerability

WordPress Plugin: ninjafirewall: CVE-2021-4451: Deserialization of Untrusted Data

Severity
8
CVSS
(AV:N/AC:M/Au:M/C:C/I:C/A:C)
Published
May 30, 2021
Added
May 15, 2025
Modified
Apr 30, 2026

Description

The NinjaFirewall plugin for WordPress is vulnerable to Authenticated PHAR Deserialization in versions up to, and including, 4.3.3. This allows authenticated attackers to perform phar deserialization on the server. This deserialization can allow other plugin or theme exploits if vulnerable software is present (WordPress, and NinjaFirewall).

Solution

ninjafirewall-plugin-cve-2021-4451
Title
Rapid7 Labs

2026 Global Threat Landscape Report

The predictive window has collapsed. Exploitation follows disclosure in days. See how attackers are accelerating and how to stay ahead.