CVE-2024-11189 is a medium-severity Stored Cross-Site Scripting (XSS) vulnerability affecting the WordPress plugin 'Social Share And Social Locker' in versions prior to 1.4.2. The vulnerability arises because the plugin fails to properly sanitize and escape certain settings, allowing high-privilege users, such as administrators, to inject malicious scripts that are stored persistently within the plugin's data. Notably, this vulnerability can be exploited even when the WordPress 'unfiltered_html' capability is disabled, such as in multisite environments, which normally restricts the ability to post unfiltered HTML. The CVSS 3.1 base score is 4.8, indicating a medium severity level, with the vector AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N. This means the attack can be launched remotely over the network with low attack complexity, but requires high privileges and user interaction. The vulnerability impacts confidentiality and integrity but not availability. Since the exploit requires an authenticated administrator to inject the payload and another user to trigger it, the scope is limited to environments where multiple users with different privilege levels exist. No known exploits are currently reported in the wild, and no official patches or updates are linked yet. The vulnerability is categorized under CWE-79, which is a common web application security flaw involving improper output encoding leading to XSS.

For European organizations using WordPress sites with the Social Share And Social Locker plugin, this vulnerability poses a risk primarily in environments where multiple users with different privilege levels operate, such as corporate intranets, membership sites, or multisite WordPress installations. An attacker with administrator access could inject malicious scripts that execute in the context of other users, potentially stealing session cookies, performing actions on behalf of users, or defacing content. While the vulnerability does not directly affect availability, the compromise of confidentiality and integrity could lead to data leakage, unauthorized actions, or reputational damage. Given the requirement for high privileges to inject the payload, the threat is more relevant in scenarios where insider threats or compromised administrator accounts exist. European organizations with strict data protection regulations (e.g., GDPR) must consider the risk of personal data exposure through such XSS attacks, which could lead to regulatory penalties and loss of customer trust.

1. Immediate mitigation involves updating the Social Share And Social Locker plugin to version 1.4.2 or later once available, as this will include proper sanitization and escaping of settings to prevent XSS. 2. Until a patch is applied, restrict administrator access to trusted personnel only and monitor admin activities for suspicious behavior. 3. Implement Content Security Policy (CSP) headers to limit the execution of unauthorized scripts on WordPress sites. 4. Use Web Application Firewalls (WAFs) that can detect and block XSS payloads in HTTP requests and responses. 5. Regularly audit and review plugin settings and content for injected scripts or anomalies. 6. Employ the principle of least privilege by limiting the number of users with administrator rights and enforcing strong authentication mechanisms such as multi-factor authentication (MFA). 7. For multisite setups, carefully manage site administrators and consider disabling or limiting the use of vulnerable plugins until patched. 8. Educate site administrators about the risks of injecting untrusted content and the importance of plugin updates.