CVE-2025-7516 is a SQL Injection vulnerability identified in version 1.0 of the code-projects Online Appointment Booking System, specifically within the /cancelbookingpatient.php file. The vulnerability arises from improper sanitization or validation of the 'appointment' parameter, which is directly used in SQL queries. An attacker can remotely exploit this flaw by manipulating the 'appointment' argument to inject malicious SQL code, potentially allowing unauthorized access to or modification of the backend database. The vulnerability requires no authentication or user interaction, making it remotely exploitable over the network. The CVSS 4.0 base score is 6.9, indicating a medium severity level, with attack vector being network (AV:N), low attack complexity (AC:L), no privileges required (PR:N), and no user interaction (UI:N). The impact on confidentiality, integrity, and availability is rated as low individually, but combined they pose a significant risk. No patches or fixes have been published yet, and no known exploits are currently in the wild, although public disclosure of the exploit code increases the risk of exploitation. This vulnerability could allow attackers to extract sensitive patient booking data, modify or delete appointments, or potentially escalate further attacks against the system or connected infrastructure.

For European organizations using the affected Online Appointment Booking System version 1.0, this vulnerability could lead to unauthorized access to sensitive patient appointment data, violating data protection regulations such as GDPR. The manipulation of appointment records could disrupt healthcare service delivery, causing operational downtime or patient care issues. Data integrity could be compromised if attackers alter or delete booking information, leading to mistrust and potential legal liabilities. Although the vulnerability does not directly allow privilege escalation or system takeover, the exposure of backend database contents could facilitate further attacks. The remote and unauthenticated nature of the exploit increases the risk for healthcare providers, clinics, or any organizations relying on this software for appointment management. Given the critical nature of healthcare data and the regulatory environment in Europe, the impact extends beyond technical damage to include reputational harm and regulatory penalties.

Organizations should immediately audit their use of the code-projects Online Appointment Booking System version 1.0 and restrict external access to the vulnerable /cancelbookingpatient.php endpoint via network controls such as firewalls or web application firewalls (WAFs). Input validation and parameterized queries should be implemented to sanitize the 'appointment' parameter, preventing SQL injection. Until an official patch is released, consider deploying virtual patching through WAF rules that detect and block SQL injection patterns targeting this parameter. Regularly monitor logs for suspicious activity related to appointment cancellation requests. If possible, upgrade to a newer, patched version of the software or switch to alternative appointment systems with verified security. Additionally, enforce strict access controls and network segmentation to limit exposure of the booking system's backend database. Conduct security awareness training for administrators to recognize and respond to potential exploitation attempts.