WordPress 4.2.21 contains two medium-severity vulnerabilities that could expose your website to security risks. While no critical vulnerabilities have been identified in this version, the two medium-level CVEs discovered require immediate attention from site administrators. Understanding these threats and implementing proper fixes is essential to protecting your site from potential attacks.
This guide breaks down both CVEs affecting WordPress 4.2.21 in simple terms, explains what risks they pose to your website, and provides step-by-step instructions to secure your installation. Whether you're running a small blog or managing multiple WordPress sites, staying informed about these vulnerabilities is crucial for your online security.
WordPress 4.2.21 is an older version of the popular WordPress content management system. Released years ago, this version powers approximately 8 known websites globally. While WordPress regularly releases updates with new features and security patches, version 4.2.21 has fallen behind the latest releases. Running older WordPress versions means you're missing out on critical security improvements and modern functionality that newer versions provide.
This particular version remains in use primarily on legacy websites or by site owners who haven't upgraded their installations. However, continuing to use outdated WordPress versions exposes your website to known security vulnerabilities that hackers actively exploit. The two medium-severity vulnerabilities found in 4.2.21 are examples of why staying current with WordPress updates is so important for protecting your site's integrity and user data.
2 CVEs found. The most critical are explained below.
The Passster password protection plugin has a vulnerability that lets users with contributor-level access or higher inject harmful code into your website. This code runs in visitors' browsers when they view protected content, potentially compromising their data or your site's reputation.
Impact: Attackers could steal visitor information, redirect users to malicious sites, or inject ads and unwanted content into your password-protected pages. Your website's trustworthiness could be severely damaged.
↗ View on NVDThe Webba Booking plugin allows administrators to unintentionally inject harmful code that executes on your website. While this requires admin access, it's a risk if your admin account is compromised or if you have untrustworthy admin users.
Impact: An attacker with admin credentials could inject malicious code affecting all your website visitors, steal data, or take control of site functionality. This could lead to customer data theft or complete site compromise.
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Securing WordPress 4.2.21 requires immediate action to patch the two medium-severity vulnerabilities discovered in this version. The CVE-2025-14865 and CVE-2021-36847 vulnerabilities could allow attackers to inject malicious scripts into your website, compromising user data and site integrity. Following our step-by-step fix guide will significantly reduce your security risk and protect your website from exploitation.
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