CVE-2025-63075 identifies a DOM-based Cross-site Scripting (XSS) vulnerability in the muffingroup Betheme WordPress theme, affecting all versions up to and including 28.1.7. This vulnerability arises due to improper neutralization of input during web page generation, allowing malicious scripts to be injected and executed in the context of a victim's browser. The attack vector is network-based with low attack complexity, requiring low privileges and user interaction, and it affects the confidentiality, integrity, and availability of affected systems. Specifically, an attacker could craft a malicious link or input that, when processed by the vulnerable Betheme theme, executes arbitrary JavaScript code in the victim's browser. This can lead to session hijacking, theft of sensitive information, unauthorized actions on behalf of the user, or defacement of the website. The vulnerability has a CVSS 3.1 base score of 6.5, reflecting medium severity with a scope change (S:C), meaning the impact extends beyond the vulnerable component. No public exploits have been reported yet, but the widespread use of Betheme in WordPress sites makes this a significant concern. The vulnerability was reserved in late October 2025 and published in December 2025, indicating recent discovery and disclosure. The lack of available patches at the time of reporting necessitates immediate mitigation efforts by administrators.

For European organizations, the impact of this DOM-based XSS vulnerability can be significant, especially for those relying on Betheme for corporate websites, e-commerce platforms, or customer portals. Exploitation could lead to unauthorized access to user sessions, leakage of confidential customer or employee data, and potential defacement or disruption of web services. This can damage brand reputation, lead to regulatory non-compliance (e.g., GDPR violations due to data breaches), and cause financial losses. The medium severity rating reflects that while exploitation requires user interaction and some privileges, the consequences affect multiple security properties and can propagate beyond the initial vulnerability. Organizations in sectors such as finance, healthcare, retail, and media, which often use WordPress themes like Betheme, are particularly at risk. Additionally, the scope change indicates that the vulnerability could affect other components or users beyond the immediate vulnerable theme, increasing potential impact.

To mitigate CVE-2025-63075, European organizations should first monitor for and apply any official patches or updates released by muffingroup for Betheme as soon as they become available. Until patches are released, administrators should implement strict Content Security Policies (CSP) to restrict the execution of unauthorized scripts and reduce the risk of XSS exploitation. Input validation and sanitization should be enforced at both client and server sides to prevent malicious input from reaching the DOM. Web Application Firewalls (WAFs) can be configured to detect and block common XSS attack patterns targeting Betheme. Additionally, organizations should educate users about the risks of clicking suspicious links and consider implementing multi-factor authentication to reduce the impact of session hijacking. Regular security audits and penetration testing focusing on web application vulnerabilities can help identify and remediate similar issues proactively. Finally, monitoring web server and application logs for unusual activity related to script injection attempts can aid in early detection of exploitation attempts.