CVE-2025-9353 is a stored Cross-Site Scripting (XSS) vulnerability identified in the Themify Builder plugin for WordPress, affecting all versions up to and including 7.6.9. The root cause is improper neutralization of input during web page generation (CWE-79), where insufficient input sanitization and output escaping allow malicious scripts to be injected into pages. The vulnerability can be exploited by authenticated users with Contributor-level access or higher, enabling them to embed arbitrary JavaScript code that executes whenever any user views the compromised page. This can lead to session hijacking, defacement, or redirection to malicious sites. The vulnerability was only partially patched in version 7.6.9, indicating that some attack vectors may still be exploitable. The CVSS v3.1 base score is 6.4 (medium severity), reflecting a network attack vector with low attack complexity, requiring privileges but no user interaction, and impacting confidentiality and integrity with a scope change. No known exploits are currently reported in the wild. The vulnerability is significant because WordPress powers a large portion of websites globally, and Themify Builder is a popular page builder plugin, increasing the attack surface. The ability for relatively low-privileged users to inject persistent scripts elevates the risk, especially in multi-user environments such as corporate or community sites where contributors are common. The partial patch suggests that site administrators should be cautious and consider additional mitigations beyond updating to 7.6.9. Overall, this vulnerability highlights the risks of insufficient input validation in web applications and the importance of strict privilege management and output encoding in CMS plugins.

For European organizations, this vulnerability poses a moderate risk primarily to websites using WordPress with the Themify Builder plugin installed. The impact includes potential compromise of user sessions, theft of sensitive information, defacement of web content, and possible distribution of malware through injected scripts. Organizations relying on WordPress for customer-facing or internal portals could suffer reputational damage, data leakage, and disruption of services. Since the vulnerability requires authenticated Contributor-level access, insider threats or compromised contributor accounts could be leveraged to exploit this flaw. In sectors with strict data protection regulations like GDPR, exploitation leading to data breaches could result in regulatory penalties and loss of customer trust. The partial patch status means that even updated sites might remain vulnerable, increasing the urgency for European organizations to assess their exposure and implement compensating controls. Additionally, the scope change in the CVSS vector indicates that the vulnerability can affect resources beyond the immediate plugin context, potentially impacting broader site integrity.

1. Immediate upgrade: Although version 7.6.9 includes a partial patch, organizations should monitor Themifyme for a fully patched release and apply updates promptly once available. 2. Privilege restriction: Limit Contributor-level access strictly to trusted users and review user roles regularly to minimize the number of users who can inject content. 3. Input validation and output encoding: Implement additional server-side input sanitization and output escaping at the application or web server level to reduce the risk of script injection. 4. Web Application Firewall (WAF): Deploy or update WAF rules to detect and block suspicious script injection attempts targeting Themify Builder parameters. 5. Content Security Policy (CSP): Enforce a strict CSP to restrict execution of unauthorized scripts, mitigating the impact of injected scripts. 6. Monitoring and logging: Enable detailed logging of content changes and user activities within WordPress to detect anomalous behavior indicative of exploitation attempts. 7. User awareness: Educate contributors about the risks of uploading or embedding untrusted content and encourage reporting of suspicious site behavior. 8. Backup and recovery: Maintain regular backups of website content to enable quick restoration in case of defacement or compromise. These measures combined will reduce the attack surface and limit the potential damage from exploitation of this vulnerability.