CVE-2025-4359 is a SQL Injection vulnerability identified in version 1.0 of the itsourcecode Gym Management System. The vulnerability exists in the /ajax.php endpoint, specifically when the 'action' parameter is set to 'delete_member' and the 'ID' argument is manipulated. This improper input validation allows an attacker to inject malicious SQL code remotely without requiring authentication or user interaction. The vulnerability can lead to unauthorized access to the backend database, potentially allowing attackers to read, modify, or delete sensitive data related to gym members and system operations. The CVSS 4.0 score is 6.9, indicating a medium severity level, with the vector showing network attack vector, low attack complexity, no privileges or user interaction needed, and limited impact on confidentiality, integrity, and availability. Although no known exploits are currently reported in the wild, the public disclosure of the vulnerability increases the risk of exploitation. The affected system is a niche gym management software, which may be deployed in small to medium-sized fitness centers for managing member data and operations.

For European organizations using the itsourcecode Gym Management System 1.0, this vulnerability poses a risk of unauthorized data exposure and manipulation. Compromise of member data could lead to privacy violations under GDPR, resulting in regulatory penalties and reputational damage. Furthermore, attackers could disrupt gym operations by deleting member records or corrupting the database, impacting business continuity. Since the vulnerability can be exploited remotely without authentication, attackers could leverage it to gain persistent access or pivot to other internal systems if network segmentation is weak. The impact is particularly significant for gyms handling sensitive personal and payment information. However, the medium severity rating and limited scope of affected systems suggest that the threat is contained to organizations using this specific software version.

Organizations should immediately assess their deployment of the itsourcecode Gym Management System version 1.0 and prioritize upgrading to a patched version once available. In the absence of an official patch, implement web application firewall (WAF) rules to detect and block SQL injection attempts targeting the /ajax.php?action=delete_member endpoint, focusing on sanitizing or blocking suspicious 'ID' parameter inputs. Conduct thorough input validation and parameterized queries in the application code to prevent injection. Network segmentation should be enforced to limit exposure of the management system to untrusted networks. Regularly audit database access logs for anomalous queries. Additionally, implement strict access controls and monitor for unusual activity to detect exploitation attempts early. Backup critical data frequently to enable recovery in case of data manipulation or deletion.