CVE-2024-3236 in Popup Builder Plugin
Summary
by MITRE • 06/17/2024
The Popup Builder WordPress plugin before 1.1.33 does not sanitise and escape some of its Notification fields, which could allow users such as contributor and above to perform Stored Cross-Site Scripting attacks.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 05/13/2025
The vulnerability identified as CVE-2024-3236 affects the Popup Builder WordPress plugin version 1.1.32 and earlier, representing a critical security flaw that enables stored cross-site scripting attacks through insufficient input sanitization and output escaping mechanisms. This issue specifically impacts notification fields within the plugin's functionality, creating a persistent security risk that can be exploited by users with contributor-level privileges or higher. The vulnerability stems from the plugin's failure to properly sanitize user-supplied data before storing it in the database and subsequently rendering it in web pages without adequate escaping mechanisms.
The technical flaw manifests in the plugin's handling of notification fields where user input is directly stored without proper sanitization processes and then displayed without appropriate HTML escaping. This creates a classic stored XSS vulnerability where malicious scripts can be injected into the notification system and subsequently executed whenever the affected page is loaded by other users. Attackers with contributor-level access or higher can leverage this weakness to inject malicious JavaScript code that will execute in the contexts of other users who view the notification content. The vulnerability is particularly concerning because it operates at the privilege level of contributors, who typically have the ability to create and edit posts and pages, making the attack vector more accessible than many other XSS vulnerabilities.
The operational impact of this vulnerability extends beyond simple script execution as it can enable sophisticated attacks including session hijacking, credential theft, and redirection to malicious sites. An attacker could craft notifications containing malicious scripts that steal cookies, redirect users to phishing pages, or even execute commands on the victim's browser. The stored nature of this vulnerability means that the malicious payloads persist in the database and can affect multiple users over time, making the impact cumulative and potentially widespread. This vulnerability undermines the trust model of WordPress sites and can lead to significant data breaches, reputation damage, and potential regulatory compliance issues for organizations running affected versions of the plugin.
Mitigation strategies should include immediate upgrading to version 1.1.33 or later of the Popup Builder plugin, which contains the necessary patches to address the sanitization and escaping issues. Organizations should also implement additional security measures such as restricting contributor privileges where possible, implementing content security policies, and monitoring notification fields for suspicious content. The vulnerability aligns with CWE-79 which specifically addresses cross-site scripting flaws, and can be categorized under ATT&CK technique T1566.001 for initial access through malicious HTML email. Regular security audits of WordPress plugins and maintaining updated security practices are essential to prevent exploitation of similar vulnerabilities in the future.