CVE-2024-4042 is a stored cross-site scripting vulnerability classified under CWE-79 that affects the pickplugins Gutenberg Blocks, Page Builder – ComboBlocks WordPress plugin, specifically versions up to and including 2.2.80. The vulnerability stems from insufficient input sanitization and output escaping of the 'class' attribute within the menu-wrap-item block. Authenticated attackers with contributor-level access or higher can exploit this flaw by injecting arbitrary JavaScript code into pages. Because the malicious script is stored, it executes every time a user accesses the infected page, potentially compromising user sessions, stealing cookies, or performing unauthorized actions on behalf of users. The vulnerability does not require user interaction beyond page access and can affect the confidentiality and integrity of site data. The CVSS 3.1 base score is 6.4, reflecting network attack vector, low attack complexity, privileges required at the contributor level, no user interaction, and a scope change due to impact on other components. No public exploits have been reported yet, but the vulnerability is significant given the widespread use of WordPress and the plugin's popularity. The lack of a patch link indicates that users must monitor vendor updates or apply manual mitigations. This vulnerability highlights the risks of insufficient input validation in web applications, especially in CMS plugins that handle dynamic content rendering.

The impact of CVE-2024-4042 is primarily on the confidentiality and integrity of affected WordPress sites and their users. Attackers with contributor-level access can inject persistent malicious scripts that execute in the context of any user visiting the compromised page, including administrators. This can lead to session hijacking, unauthorized actions, data theft, or defacement. For organizations, this can result in reputational damage, loss of customer trust, and potential regulatory consequences if user data is compromised. Since WordPress powers a significant portion of the web, and the affected plugin is widely used for page building, the scope of impact is broad. The vulnerability does not affect availability directly but can indirectly cause service disruption if exploited to escalate privileges or inject malware. Attackers do require some level of authenticated access, which limits exploitation to environments where contributor accounts exist or can be compromised. However, many WordPress sites allow contributor roles for content creation, increasing risk. The vulnerability is particularly concerning for sites with high traffic or sensitive data, such as e-commerce, news, or corporate portals.

To mitigate CVE-2024-4042, organizations should first update the pickplugins Gutenberg Blocks, Page Builder – ComboBlocks plugin to a patched version once released by the vendor. Until a patch is available, restrict contributor-level access strictly to trusted users and audit existing contributor accounts for suspicious activity. Implement web application firewall (WAF) rules to detect and block malicious payloads targeting the 'class' attribute in menu-wrap-item blocks. Employ Content Security Policy (CSP) headers to limit script execution sources, reducing the impact of injected scripts. Regularly scan WordPress installations with security plugins that detect XSS vulnerabilities or anomalous content injections. Educate site administrators and content creators about the risks of XSS and the importance of input validation. Review and harden user role permissions to minimize unnecessary privileges. Monitor logs for unusual page edits or script injections. Finally, consider isolating critical administrative interfaces and enabling multi-factor authentication to reduce the risk of account compromise that could lead to exploitation.