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 enables an attacker to manipulate backend database queries, potentially leading to unauthorized data access, data modification, or even complete compromise of the underlying database. The vulnerability is remotely exploitable over the network with low attack complexity and no privileges required, which increases the risk of exploitation. Although the CVSS 4.0 score is 6.9 (medium severity), the nature of SQL injection vulnerabilities typically warrants heightened concern due to the potential for data breaches and system compromise. The vulnerability affects only version 1.0 of the product, and no official patches or mitigations have been published yet. There are no known exploits in the wild at the time of reporting, but public disclosure of the exploit code increases the risk of imminent attacks. The vulnerability impacts confidentiality, integrity, and availability of the affected system's data, with partial impact on each (low to medium impact on confidentiality, integrity, and availability).

For European organizations using the code-projects Online Appointment Booking System version 1.0, this vulnerability poses significant risks. Appointment booking systems often handle sensitive personal data, including client identities, contact information, appointment details, and potentially payment information. Exploitation could lead to unauthorized data disclosure violating GDPR and other data protection regulations, resulting in legal penalties and reputational damage. Attackers could also manipulate appointment data, causing operational disruptions and loss of trust. Given the remote and unauthenticated nature of the exploit, attackers can target vulnerable systems en masse, increasing the risk of widespread compromise. The medium CVSS score may underestimate the real-world impact, as SQL injection can be leveraged for privilege escalation or pivoting within networks. Organizations relying on this software for customer-facing services may face service interruptions and data breaches, impacting business continuity and customer confidence.

Immediate mitigation steps include: 1) Restricting network access to the /getDay.php endpoint by implementing web application firewalls (WAFs) with SQL injection detection and blocking rules tailored to the 'cidval' parameter. 2) Applying input validation and parameterized queries or prepared statements in the codebase to sanitize the 'cidval' parameter and prevent injection. 3) If source code modification is not immediately possible, deploying virtual patching via WAF or reverse proxy rules to block suspicious payloads targeting 'cidval'. 4) Conducting thorough security testing and code review of the appointment booking system to identify and remediate similar injection points. 5) Monitoring logs for unusual query patterns or repeated access attempts to /getDay.php. 6) Planning for an upgrade or patch deployment from the vendor once available. 7) Implementing strict database user permissions to limit the impact of any successful injection. 8) Educating IT and security teams about the vulnerability and ensuring incident response readiness.