CVE-2024-11881 is a stored cross-site scripting vulnerability identified in the Easy Waveform Player plugin for WordPress, affecting all versions up to and including 1.2.0. The vulnerability stems from insufficient sanitization and escaping of user-supplied input in the 'easywaveformplayer' shortcode attributes. Specifically, authenticated users with contributor-level permissions or higher can inject arbitrary JavaScript code into pages or posts via these shortcode attributes. Because the malicious script is stored persistently in the WordPress database, it executes automatically whenever any user, including administrators or visitors, accesses the compromised page. The vulnerability exploits improper neutralization of input during web page generation, classified under CWE-79. The CVSS 3.1 base score of 6.4 indicates a medium severity, with network attack vector, low attack complexity, privileges required (limited to authenticated contributors), no user interaction needed, and a scope change due to potential impact on other users. The impact includes potential confidentiality and integrity breaches such as session hijacking, defacement, or unauthorized actions performed in the context of the victim's browser. No patches or official fixes have been linked yet, and no active exploitation has been reported, but the vulnerability poses a significant risk to WordPress sites using this plugin without proper mitigation.

The primary impact of CVE-2024-11881 is the compromise of confidentiality and integrity for WordPress sites using the Easy Waveform Player plugin. An attacker with contributor-level access can inject malicious scripts that execute in the browsers of any user viewing the infected page, potentially leading to session hijacking, credential theft, unauthorized actions, or defacement. This can undermine user trust, lead to data breaches, and facilitate further attacks such as privilege escalation or malware distribution. Since the vulnerability requires authenticated access, it limits exposure to sites with weak user management or where contributors are not fully trusted. However, the scope includes all users who visit the infected pages, including administrators, increasing the risk of severe consequences. The lack of availability impact means the site remains operational, but the integrity and confidentiality risks are significant. Organizations relying on this plugin may face reputational damage, regulatory compliance issues, and operational disruption if exploited.

To mitigate CVE-2024-11881, organizations should first check for and apply any available updates or patches from the plugin vendor as soon as they are released. In the absence of an official patch, administrators should consider temporarily disabling or uninstalling the Easy Waveform Player plugin to eliminate the attack vector. Restrict contributor-level access strictly to trusted users and audit existing contributor accounts for suspicious activity. Implement a Web Application Firewall (WAF) with rules to detect and block common XSS payloads targeting the shortcode parameters. Employ Content Security Policy (CSP) headers to restrict script execution sources and reduce the impact of injected scripts. Regularly scan the WordPress site for injected malicious scripts or unauthorized content changes, especially in pages using the shortcode. Educate content contributors about safe input practices and monitor logs for unusual shortcode usage patterns. Finally, consider hardening WordPress security by enforcing multi-factor authentication and minimizing plugin usage to reduce the attack surface.