CVE-2025-4363 is a SQL Injection vulnerability identified in version 1.0 of the itsourcecode Gym Management System. The vulnerability resides in the /ajax.php endpoint, specifically when handling the 'rid' parameter in the 'end_membership' action. An attacker can manipulate this parameter to inject malicious SQL code, which the backend database executes. This flaw allows remote attackers to execute arbitrary SQL commands without any authentication or user interaction, as indicated by the CVSS vector (AV:N/AC:L/AT:N/PR:N/UI:N). The vulnerability impacts the confidentiality, integrity, and availability of the affected system, as attackers could extract sensitive data, modify or delete records, or disrupt service operations. Although the CVSS score is 6.9 (medium severity), the vulnerability is classified as critical in the description, likely due to the ease of exploitation and potential impact. No official patches have been released yet, and no known exploits are reported in the wild, but public disclosure increases the risk of exploitation. The vulnerability affects only version 1.0 of the product, which is a niche gym management software solution, typically used by fitness centers to manage memberships and related operations.

For European organizations using the itsourcecode Gym Management System 1.0, this vulnerability poses a significant risk. Exploitation could lead to unauthorized access to member data, including personal and payment information, violating GDPR and other data protection regulations. The integrity of membership records could be compromised, leading to financial discrepancies or fraudulent membership terminations. Availability of the system could also be affected, disrupting gym operations and customer service. Such incidents could damage organizational reputation and result in regulatory fines. Given the critical nature of the vulnerability and the lack of authentication requirements, even small or medium-sized gyms could be targeted, amplifying the impact across the sector.

Organizations should immediately audit their use of the itsourcecode Gym Management System and identify any instances of version 1.0. Until an official patch is released, it is recommended to implement web application firewall (WAF) rules specifically targeting the 'rid' parameter in the /ajax.php?action=end_membership endpoint to detect and block SQL injection attempts. Input validation and parameterized queries should be enforced at the application level if source code access is available. Network segmentation can limit exposure of the vulnerable system. Monitoring and logging of database queries and web requests should be enhanced to detect suspicious activity. Additionally, organizations should prepare incident response plans for potential data breaches and notify affected stakeholders promptly if exploitation occurs. Regular backups of the database should be maintained to enable recovery from data tampering or loss.