The NGG Smart Image Search plugin for WordPress, widely used for enhanced image search functionality, suffers from a stored cross-site scripting (XSS) vulnerability identified as CVE-2024-13658. This vulnerability is due to improper neutralization of input during web page generation (CWE-79), specifically within the 'hr_SIS_nextgen_searchbox' shortcode. The plugin fails to adequately sanitize and escape user-supplied attributes, allowing authenticated users with contributor-level or higher permissions to inject arbitrary JavaScript code. Because the malicious script is stored and rendered on pages accessed by other users, it can execute in the context of their browsers without requiring further interaction. The vulnerability impacts all versions up to and including 3.2.1. The CVSS 3.1 base score of 6.4 reflects a network attack vector with low attack complexity, requiring privileges but no user interaction, and resulting in limited confidentiality and integrity impacts but no availability impact. The scope is changed, indicating that the vulnerability affects resources beyond the vulnerable component. Although no known exploits are currently in the wild, the vulnerability poses a significant risk due to the potential for session hijacking, credential theft, or unauthorized actions within the WordPress environment. The vulnerability was publicly disclosed in February 2025, and no official patches have been linked yet, emphasizing the need for immediate mitigation.

This vulnerability allows authenticated users with contributor-level access or higher to inject persistent malicious scripts into WordPress pages via the NGG Smart Image Search plugin. The impact includes potential theft of cookies, session tokens, or other sensitive information from users who view the infected pages. Attackers could perform actions on behalf of other users, including administrators, leading to privilege escalation or site compromise. Since WordPress powers a significant portion of the web, sites using this plugin are at risk of defacement, data leakage, or further malware distribution. The attack requires authentication but no user interaction, making it easier for insiders or compromised accounts to exploit. The confidentiality and integrity of user data and site content are at risk, though availability is not directly affected. Organizations with multi-user WordPress environments, especially those allowing contributor-level access broadly, face increased risk. The vulnerability could also be leveraged in targeted attacks against high-value websites or used as a foothold for further exploitation within the hosting environment.

1. Immediately restrict contributor-level and higher permissions to trusted users only, minimizing the risk of malicious input. 2. Monitor and audit user-generated content, especially content created via the 'hr_SIS_nextgen_searchbox' shortcode, for suspicious scripts or anomalies. 3. Apply strict Content Security Policy (CSP) headers to limit the execution of unauthorized scripts on affected sites. 4. If possible, disable or remove the NGG Smart Image Search plugin until an official patch is released. 5. Implement web application firewall (WAF) rules to detect and block attempts to inject or execute malicious scripts via this plugin. 6. Educate site administrators and contributors about the risks of XSS and safe content creation practices. 7. Regularly update WordPress and all plugins, and monitor vendor announcements for patches addressing this vulnerability. 8. Consider employing security plugins that sanitize user inputs and outputs to add an additional layer of defense. 9. Review and harden user roles and permissions to limit the number of users who can exploit this vulnerability. 10. Conduct regular security assessments and penetration tests focusing on plugin vulnerabilities and user input handling.