CVE-2024-4002 is a stored Cross-Site Scripting (XSS) vulnerability identified in the WordPress plugin 'Carousel, Slider, Gallery by WP Carousel' prior to version 2.6.9. The root cause is the plugin's failure to properly sanitize and escape certain settings, which allows high-privilege users, such as administrators, to inject malicious JavaScript code that is stored persistently within the plugin's configuration. This vulnerability is notable because it can be exploited even when the WordPress capability 'unfiltered_html' is disabled, a common security measure in multisite WordPress environments to restrict HTML content editing. Exploitation requires an attacker to have administrator-level access to the WordPress backend, which limits the attack vector primarily to insider threats or compromised admin accounts. The injected scripts execute in the context of users who view the affected plugin's output, potentially leading to session hijacking, privilege escalation, or further attacks against site visitors or administrators. The CVSS 3.1 base score is 3.5, indicating low severity due to the requirement for high privileges and user interaction to trigger the vulnerability, and the limited impact on confidentiality and integrity. No availability impact is noted. No public exploits have been reported yet, but the vulnerability is published and recognized by WPScan and CISA. The vulnerability affects all versions before 2.6.9, and no patch links are provided in the source, but updating to the fixed version is recommended. This vulnerability highlights the importance of proper input sanitization and escaping in WordPress plugins, especially those that handle user-configurable settings.

For European organizations, the impact of CVE-2024-4002 is primarily related to the risk of stored XSS attacks within WordPress sites using the vulnerable plugin. If an attacker gains administrator access, they could inject malicious scripts that execute in the browsers of other administrators or users who view the affected content. This could lead to session hijacking, theft of sensitive information, or further compromise of the WordPress environment. While the vulnerability requires high privileges and user interaction, the risk is significant in environments with multiple administrators or where admin credentials may be compromised. European organizations running multisite WordPress installations are particularly at risk because the vulnerability bypasses the unfiltered_html restriction commonly used in such setups. The impact on confidentiality and integrity is low but non-negligible, especially for organizations handling sensitive data or providing critical services via WordPress. There is no direct impact on availability. The absence of known exploits in the wild reduces immediate risk but does not eliminate the need for prompt remediation. Failure to address this vulnerability could lead to reputational damage, regulatory scrutiny under GDPR if personal data is compromised, and potential lateral movement within compromised networks.

1. Immediately update the 'Carousel, Slider, Gallery by WP Carousel' plugin to version 2.6.9 or later where the vulnerability is fixed. 2. Restrict administrator access to trusted personnel only and enforce strong authentication mechanisms such as multi-factor authentication (MFA) to reduce the risk of compromised admin accounts. 3. Regularly audit WordPress user roles and permissions to ensure no unauthorized users have elevated privileges. 4. Implement Content Security Policy (CSP) headers to limit the impact of potential XSS by restricting the sources from which scripts can be loaded and executed. 5. Monitor WordPress logs and plugin settings for unusual changes or injected scripts that could indicate exploitation attempts. 6. For multisite WordPress environments, review and tighten capability settings and consider additional plugin hardening measures. 7. Educate administrators about the risks of XSS and the importance of cautious input handling within the WordPress admin interface. 8. Use security plugins that can detect and block XSS payloads or suspicious activity within the WordPress dashboard. 9. Backup WordPress sites regularly to enable quick recovery if compromise occurs. 10. Stay informed about updates and advisories related to WordPress plugins and promptly apply security patches.