CVE-2025-5947 is a critical security vulnerability affecting the Service Finder Bookings plugin for WordPress, developed by aonetheme. This vulnerability is classified under CWE-639, which pertains to authorization bypass through user-controlled keys. The flaw exists in all versions of the plugin up to and including version 6.0. The root cause is improper validation of a user's cookie value within the service_finder_switch_back() function. Specifically, the plugin fails to verify the authenticity and integrity of the cookie before using it to authenticate a user session. This allows an unauthenticated attacker to manipulate the cookie value and effectively bypass authentication controls, enabling them to log in as any user on the system, including administrators. The vulnerability has a CVSS v3.1 base score of 9.8, indicating critical severity, with attack vector being network-based, no required privileges or user interaction, and full impact on confidentiality, integrity, and availability. Although no known exploits are currently reported in the wild, the ease of exploitation and the potential for complete system compromise make this a highly dangerous vulnerability. Given the widespread use of WordPress and the popularity of the Service Finder Bookings plugin for managing appointments and bookings, this vulnerability poses a significant risk to websites relying on this plugin for business operations.

For European organizations, the impact of this vulnerability could be severe. Many businesses, including SMEs and service providers, use WordPress with booking plugins to manage customer appointments and services. Exploitation of this vulnerability would allow attackers to gain unauthorized administrative access, leading to potential data breaches involving personal customer data, financial information, and internal business data. This could result in reputational damage, regulatory penalties under GDPR for data protection violations, and operational disruption if attackers modify or delete critical booking data or inject malicious content. The ability to escalate privileges without authentication means attackers can operate stealthily and persistently. Furthermore, compromised websites could be used as a launchpad for further attacks against customers or partners, amplifying the impact. The critical nature of this vulnerability necessitates urgent attention from European organizations using the affected plugin to prevent exploitation and mitigate risks to their digital assets and customer trust.

Immediate mitigation steps include: 1) Updating the Service Finder Bookings plugin to a patched version once available from the vendor. Since no patch links are currently provided, organizations should monitor aonetheme's official channels for updates. 2) In the interim, disable or deactivate the Service Finder Bookings plugin to prevent exploitation. 3) Implement Web Application Firewall (WAF) rules to detect and block suspicious requests attempting to exploit cookie manipulation or unauthorized login attempts related to this plugin. 4) Conduct a thorough audit of user accounts and access logs to detect any unauthorized access or suspicious activity. 5) Enforce strict cookie security policies, including HttpOnly and Secure flags, to reduce the risk of cookie tampering. 6) Limit administrative access to trusted IP addresses where feasible and enforce multi-factor authentication (MFA) on all admin accounts to reduce the impact of compromised credentials. 7) Educate site administrators on monitoring for unusual login patterns and ensure regular backups are maintained to enable recovery from potential compromises. These steps go beyond generic advice by focusing on immediate containment, detection, and preparation for patch deployment.