CVE-2024-3725 is a stored cross-site scripting vulnerability identified in the Otter Blocks – Gutenberg Blocks, Page Builder for Gutenberg Editor & FSE WordPress plugin, maintained by themeisle. The vulnerability exists in all versions up to and including 2.6.9, specifically in the Post Grid widget component. The root cause is the improper neutralization of input during web page generation (CWE-79), where user-supplied attributes such as 'titleTag' are not sufficiently sanitized or escaped before being rendered on pages. This allows an authenticated attacker with contributor-level privileges or higher to inject arbitrary JavaScript code that is stored persistently and executed in the browsers of users who visit the affected pages. The attack vector is remote and network-based, requiring only low complexity and no user interaction to trigger once the malicious content is injected. The vulnerability impacts the confidentiality and integrity of user sessions and data by enabling script execution in the context of the victim’s browser, potentially leading to session hijacking, unauthorized actions, or data exfiltration. Although no known exploits have been reported in the wild, the vulnerability’s presence in a widely used WordPress plugin makes it a significant risk. The CVSS v3.1 base score is 6.4, categorized as medium severity, reflecting the need for timely remediation. The vulnerability was publicly disclosed on May 2, 2024, and is tracked under CWE-79. No official patches were linked at the time of disclosure, so users must monitor vendor updates or apply manual mitigations.

The impact of CVE-2024-3725 is primarily on the confidentiality and integrity of websites using the vulnerable Otter Blocks plugin. Successful exploitation allows attackers with contributor-level access to inject persistent malicious scripts that execute in the browsers of site visitors and administrators. This can lead to session hijacking, theft of sensitive information such as cookies or credentials, unauthorized actions performed on behalf of users, and potential defacement or redirection attacks. Since the vulnerability requires authenticated access, the risk is somewhat mitigated by access controls; however, contributor-level permissions are common in many WordPress sites, increasing the attack surface. The vulnerability does not affect availability directly but can undermine user trust and site integrity. Organizations relying on this plugin for content management and page building face reputational damage and potential data breaches if exploited. The widespread use of WordPress and the popularity of the Gutenberg editor and its extensions mean that many websites globally could be affected, especially those that do not promptly update or restrict contributor privileges.

To mitigate CVE-2024-3725, organizations should immediately update the Otter Blocks plugin to a patched version once available from the vendor. Until an official patch is released, administrators should restrict contributor-level permissions to trusted users only and audit existing user roles to minimize risk. Implementing a Web Application Firewall (WAF) with rules to detect and block suspicious script injections targeting the 'titleTag' attribute or Post Grid widget parameters can provide interim protection. Site owners should also enable Content Security Policy (CSP) headers to limit the execution of unauthorized scripts and monitor logs for unusual activity indicative of exploitation attempts. Regularly scanning the website for injected scripts and performing security audits on user-generated content can help detect exploitation early. Additionally, educating content contributors about safe input practices and enforcing strict input validation on the server side can reduce the likelihood of malicious code injection. Backup strategies should be enhanced to allow quick restoration in case of compromise.