CVE-2025-63011 identifies a DOM-based Cross-site Scripting (XSS) vulnerability in the WP Hotel Booking plugin developed by ThimPress for WordPress websites. The vulnerability stems from improper neutralization of user-supplied input during the generation of web pages, which allows malicious scripts to be injected and executed within the victim's browser environment. This type of XSS is client-side, occurring when the browser processes unsafe data embedded in the DOM, often via URL parameters or other user-controllable inputs. The affected versions include all releases up to and including 2.2.7. Exploiting this vulnerability does not require authentication, making it accessible to remote attackers who can craft malicious URLs or payloads and trick users into interacting with them. Successful exploitation can lead to theft of session cookies, user credentials, or execution of unauthorized actions within the context of the victim's session. Although no public exploits have been reported yet, the vulnerability's presence in a widely used WordPress plugin for hotel booking systems increases its risk profile. The lack of a CVSS score indicates that the vulnerability is newly disclosed, but its characteristics suggest a significant threat to confidentiality and integrity of affected systems. The plugin's role in managing bookings and potentially sensitive customer data further elevates the risk. The vulnerability's discovery date is December 9, 2025, with the CVE reserved on October 24, 2025. No official patches or mitigations have been linked yet, emphasizing the need for vigilance and proactive defense.

For European organizations, especially those in the hospitality and tourism sectors relying on WordPress and the WP Hotel Booking plugin, this vulnerability could lead to significant data breaches involving customer personal information and booking details. Attackers exploiting this XSS flaw can hijack user sessions, steal authentication tokens, or perform unauthorized actions on behalf of legitimate users, potentially resulting in financial fraud or reputational damage. The compromise of booking systems can disrupt operations and erode customer trust. Given the widespread use of WordPress in Europe and the importance of tourism to many European economies, the impact could be broad and severe. Furthermore, regulatory frameworks such as GDPR impose strict requirements on protecting personal data, and exploitation of this vulnerability could lead to compliance violations and associated penalties. The lack of known exploits currently reduces immediate risk but does not diminish the potential impact once exploitation techniques become available.

Organizations should prioritize monitoring for updates from ThimPress and apply patches for WP Hotel Booking promptly once released. Until a patch is available, administrators should implement strict input validation and sanitization on all user inputs, especially those reflected in the DOM or URLs. Deploying Content Security Policies (CSP) can help restrict the execution of unauthorized scripts and mitigate the impact of XSS attacks. Web Application Firewalls (WAFs) configured to detect and block XSS payloads should be employed. Regular security audits and penetration testing focusing on plugin vulnerabilities are recommended. Additionally, educating users about the risks of clicking on suspicious links and implementing multi-factor authentication can reduce the risk of session hijacking. Backup procedures should be reviewed to ensure rapid recovery in case of compromise. Finally, monitoring web logs and user activity for anomalies can provide early detection of exploitation attempts.