CVE-2025-4487 is a critical SQL Injection vulnerability identified in version 1.0 of the itsourcecode Gym Management System. The vulnerability resides in the /ajax.php endpoint, specifically when the 'action' parameter is set to 'delete_member' and the 'ID' argument is manipulated. An attacker can exploit this flaw remotely without any authentication or user interaction, by injecting malicious SQL code through the 'ID' parameter. This injection can lead to unauthorized access to the backend database, allowing attackers to read, modify, or delete sensitive data related to gym members, potentially including personal information, membership details, and payment records. The CVSS 4.0 base score is 6.9, indicating a medium severity level, primarily due to limited impact on confidentiality, integrity, and availability (each rated low), but with ease of exploitation (no privileges or user interaction required) and network attack vector. Although no known exploits have been reported in the wild yet, the public disclosure of the exploit code increases the risk of active exploitation. The vulnerability does not require authentication, making any exposed installation of the affected version vulnerable to remote attacks. The lack of available patches or mitigation from the vendor as of the publication date further exacerbates the risk. This vulnerability highlights the importance of secure coding practices, particularly input validation and parameterized queries, to prevent SQL injection attacks in web applications managing sensitive user data.

For European organizations using the itsourcecode Gym Management System version 1.0, this vulnerability poses a significant risk to the confidentiality and integrity of member data. Unauthorized database access could lead to data breaches involving personal identifiable information (PII), financial data, and membership records, potentially violating GDPR and other data protection regulations. The compromise of such data could result in reputational damage, regulatory fines, and loss of customer trust. Additionally, attackers could manipulate or delete membership data, disrupting business operations and availability of services. Given the remote and unauthenticated nature of the exploit, attackers can easily target exposed systems over the internet, increasing the likelihood of widespread exploitation if the system is publicly accessible. European gyms and fitness centers relying on this software without adequate network protections or timely patching are particularly vulnerable. The medium CVSS score reflects moderate impact but the critical nature of data involved and regulatory environment in Europe elevates the practical impact severity. Organizations may also face legal consequences if they fail to protect member data adequately.

1. Immediate mitigation should include restricting external access to the /ajax.php endpoint, especially the 'delete_member' action, by implementing network-level controls such as firewalls or VPN access to limit exposure. 2. Employ Web Application Firewalls (WAFs) with rules to detect and block SQL injection attempts targeting the vulnerable parameter. 3. If possible, disable or remove the vulnerable functionality until a patch or update is available. 4. Review and sanitize all inputs rigorously, applying parameterized queries or prepared statements to prevent SQL injection. 5. Monitor logs for suspicious activity related to the 'delete_member' action or unusual database queries. 6. Engage with the vendor or community to obtain patches or updated versions addressing this vulnerability. 7. Conduct a thorough security audit of the application and underlying database to identify and remediate any other injection points. 8. Educate staff on incident response procedures in case of a breach. 9. Ensure regular backups of critical data are maintained and tested for recovery to mitigate potential data loss.