CVE-2024-9458 is a Stored Cross-Site Scripting (XSS) vulnerability classified under CWE-79 affecting the Reservit Hotel WordPress plugin versions prior to 3.0. The root cause is the plugin's failure to properly sanitize and escape certain settings inputs, which allows high privilege users, such as administrators, to inject malicious JavaScript code into the plugin's stored data. This vulnerability is notable because it bypasses the typical WordPress security control of the unfiltered_html capability, which is often disabled in multisite environments to restrict HTML input. The vulnerability requires an attacker to have administrator-level privileges and some user interaction to trigger the malicious script execution. The CVSS 3.1 base score is 4.8 (medium severity), reflecting the network attack vector, low attack complexity, high privileges required, and user interaction needed. The impact includes limited confidentiality and integrity compromise, such as session hijacking or unauthorized actions performed via the injected script, but no direct impact on availability. No public exploits have been reported yet, but the vulnerability is published and should be addressed promptly. Since the plugin is used in WordPress environments, the attack surface includes websites running Reservit Hotel plugin, especially those in multisite configurations where unfiltered_html is disabled but this vulnerability still applies.

For European organizations, the impact of CVE-2024-9458 depends on their use of the Reservit Hotel WordPress plugin. Organizations operating hospitality or hotel booking websites using this plugin are at risk of stored XSS attacks that could compromise administrative accounts and site integrity. This could lead to unauthorized administrative actions, data leakage, or defacement, undermining customer trust and potentially violating data protection regulations such as GDPR if personal data is exposed. The vulnerability requires admin-level access, so insider threats or compromised admin credentials could be leveraged by attackers. While the direct availability impact is none, the integrity and confidentiality risks could disrupt business operations and damage reputation. Multisite WordPress setups common in larger organizations or agencies managing multiple hotel sites are particularly vulnerable due to the bypass of unfiltered_html restrictions. Given the hospitality sector's importance in Europe and the increasing reliance on online booking systems, this vulnerability could have significant operational and compliance consequences if exploited.

To mitigate CVE-2024-9458, European organizations should immediately upgrade the Reservit Hotel plugin to version 3.0 or later once available, as this will include proper sanitization and escaping of settings inputs. Until a patch is released, organizations should restrict administrator access to trusted personnel only and enforce strong authentication mechanisms such as multi-factor authentication to reduce the risk of credential compromise. Regularly audit admin accounts and plugin settings for suspicious changes. Implement Content Security Policy (CSP) headers to limit the impact of potential XSS payloads by restricting script execution sources. Employ Web Application Firewalls (WAFs) with custom rules to detect and block malicious input patterns targeting the plugin. For multisite WordPress environments, review and tighten user role permissions and consider disabling or limiting plugin usage on sites where it is not essential. Conduct security awareness training for administrators to recognize and avoid executing suspicious scripts or links. Finally, monitor logs and website behavior for signs of XSS exploitation attempts.