CVE-2025-7517 is a critical SQL Injection vulnerability identified in version 1.0 of the code-projects Online Appointment Booking System. The vulnerability arises from improper sanitization of the 'cidval' parameter in the /getDay.php endpoint, allowing an attacker to inject malicious SQL code remotely without any authentication or user interaction. Exploiting this flaw could enable an attacker to manipulate backend database queries, potentially leading to unauthorized data access, data modification, or even complete compromise of the database. The vulnerability has been publicly disclosed, increasing the risk of exploitation, although no confirmed exploits have been observed in the wild yet. The CVSS 4.0 base score is 6.9 (medium severity), reflecting the network attack vector, low complexity, no privileges or user interaction required, but with limited impact on confidentiality, integrity, and availability. The vulnerability affects only version 1.0 of the product, which is an online appointment booking system commonly used by organizations to manage scheduling and client appointments.

For European organizations using the affected Online Appointment Booking System version 1.0, this vulnerability poses a significant risk to the confidentiality and integrity of client and organizational data. Successful exploitation could lead to unauthorized disclosure of sensitive appointment and client information, manipulation or deletion of booking data, and potential disruption of scheduling services. This could result in reputational damage, regulatory non-compliance (especially under GDPR), and operational downtime. Since the system is often integrated with customer management workflows, the impact could cascade into other business processes. The public disclosure of the vulnerability increases the urgency for European entities to assess and remediate the issue promptly to prevent potential data breaches or service interruptions.

Given the absence of an official patch, European organizations should immediately implement the following mitigations: 1) Apply input validation and sanitization on the 'cidval' parameter at the web application firewall (WAF) or reverse proxy level to block malicious SQL payloads. 2) Employ parameterized queries or prepared statements in the application code to prevent SQL injection if source code access and modification are possible. 3) Restrict database user permissions to the minimum necessary to limit the impact of a successful injection. 4) Monitor web server and database logs for suspicious activities targeting /getDay.php or unusual query patterns. 5) Consider temporarily disabling or restricting access to the vulnerable endpoint until a vendor patch or update is available. 6) Conduct a thorough security review of the entire appointment booking system to identify and remediate other potential injection points. 7) Educate IT and security teams about the vulnerability and ensure incident response plans are updated to handle potential exploitation scenarios.