CVE-2024-11749 is a stored Cross-Site Scripting (XSS) vulnerability identified in the App Embed plugin for WordPress, specifically affecting all versions up to and including 2.3.2. The root cause is insufficient sanitization and escaping of user-supplied input within the plugin’s 'appizy' shortcode attributes. This flaw allows authenticated users with contributor-level permissions or higher to inject arbitrary JavaScript code into pages. Because the injected scripts are stored persistently, they execute every time any user accesses the compromised page, potentially leading to session hijacking, privilege escalation, or unauthorized actions performed on behalf of users. The vulnerability is exploitable remotely over the network without user interaction but requires the attacker to have authenticated access with contributor or higher privileges, which lowers the attack complexity. The CVSS 3.1 score of 6.4 reflects a medium severity, with impact on confidentiality and integrity but no direct effect on availability. No public exploits have been reported yet, but the vulnerability represents a significant risk for WordPress sites using this plugin, especially those with multiple contributors or editors. The vulnerability falls under CWE-79, a common and well-understood web application security weakness. Mitigation requires patching the plugin or applying strict input validation and output encoding to prevent script injection.

The primary impact of this vulnerability is the compromise of confidentiality and integrity within affected WordPress sites. An attacker with contributor-level access can inject malicious scripts that execute in the context of other users’ browsers, potentially stealing session cookies, performing unauthorized actions, or defacing content. This can lead to account takeover, data leakage, or further exploitation of the site and its users. Since the vulnerability is stored XSS, the malicious payload persists and affects all visitors to the infected page, amplifying the attack surface. Organizations relying on the App Embed plugin risk reputational damage, loss of user trust, and potential regulatory consequences if sensitive data is exposed. The requirement for authenticated access limits the scope somewhat but does not eliminate risk, especially in environments with many contributors or less stringent user management. The vulnerability does not affect availability directly but can be leveraged as part of multi-stage attacks.

To mitigate CVE-2024-11749, organizations should immediately update the App Embed plugin to a version that addresses this vulnerability once available. If an official patch is not yet released, administrators should restrict contributor-level access to trusted users only and consider temporarily disabling the plugin or the 'appizy' shortcode functionality. Implementing strict input validation and output encoding on all user-supplied shortcode attributes can prevent script injection. Employing a Web Application Firewall (WAF) with rules to detect and block XSS payloads targeting this plugin can provide interim protection. Regularly auditing user roles and permissions to minimize the number of users with contributor or higher privileges reduces the attack surface. Monitoring website content for unexpected script injections and unusual behavior can help detect exploitation attempts early. Finally, educating content contributors about secure content practices and the risks of injecting untrusted code is recommended.