CVE-2024-12588 is a stored cross-site scripting (XSS) vulnerability identified in the Shortcodes and extra features for Phlox theme WordPress plugin, specifically within its Staff widget component. The vulnerability stems from insufficient sanitization and escaping of user-supplied attributes during web page generation, classified under CWE-79. Authenticated attackers with contributor-level privileges or higher can exploit this flaw by injecting arbitrary JavaScript code into pages managed by the plugin. Because the malicious scripts are stored persistently, they execute automatically whenever any user accesses the infected page, potentially compromising user sessions, stealing credentials, or performing unauthorized actions on behalf of users. The vulnerability affects all plugin versions up to and including 2.16.4. The CVSS 3.1 base score is 6.4, reflecting a medium severity with network attack vector, low attack complexity, and privileges required but no user interaction needed. The scope is changed (S:C), indicating that exploitation can affect resources beyond the vulnerable component. No public exploits have been reported yet, but the vulnerability poses a significant risk due to the widespread use of WordPress and the plugin’s role in content presentation. The flaw highlights the critical need for proper input validation and output encoding in web applications, especially those that allow user-generated content or contributions.

The impact of CVE-2024-12588 can be significant for organizations using the affected WordPress plugin. Successful exploitation allows attackers with contributor-level access to inject persistent malicious scripts, which execute in the browsers of all users visiting the compromised pages. This can lead to session hijacking, theft of sensitive information such as authentication tokens or personal data, unauthorized actions performed on behalf of users, and website defacement. Since the vulnerability does not require user interaction, the risk of automated exploitation is higher once an attacker gains the necessary privileges. Organizations with multiple contributors or editors are particularly vulnerable, as insider threats or compromised contributor accounts can be leveraged. The compromise of user trust and potential data breaches can result in reputational damage, regulatory penalties, and operational disruptions. Although no known exploits are currently reported, the medium severity score and ease of exploitation warrant prompt remediation to prevent future attacks.

To mitigate CVE-2024-12588, organizations should immediately update the Shortcodes and extra features for Phlox theme plugin to a patched version once available. In the absence of an official patch, administrators should restrict contributor-level access and above to trusted users only, minimizing the risk of malicious script injection. Implementing a Web Application Firewall (WAF) with rules to detect and block common XSS payloads targeting the Staff widget can provide temporary protection. Additionally, site owners should audit existing content generated via the plugin for injected scripts and remove any suspicious code. Employing Content Security Policy (CSP) headers can help limit the impact of injected scripts by restricting script sources and execution contexts. Regular security training for contributors on safe content practices and monitoring user activity for anomalous behavior can further reduce risk. Finally, developers should review and improve input validation and output encoding in the plugin’s codebase to prevent similar vulnerabilities in the future.