CVE-2025-6420 is a SQL Injection vulnerability identified in version 1.0 of the Simple Online Hotel Reservation System developed by code-projects. The vulnerability exists in the /admin/add_room.php file, specifically in the handling of the 'room_type' parameter. An attacker can remotely exploit this flaw by manipulating the 'room_type' argument to inject malicious SQL code. This injection can lead to unauthorized access or modification of the backend database, potentially allowing attackers to retrieve sensitive information, alter data, or disrupt the application's normal operations. The vulnerability requires no authentication or user interaction, making it accessible for remote exploitation. The CVSS 4.0 base score is 6.9, categorized as medium severity, reflecting the ease of exploitation (no privileges or user interaction needed) but limited scope and impact on confidentiality, integrity, and availability (each rated low). No official patches have been released yet, and while the exploit has been publicly disclosed, there are no known active exploit campaigns in the wild at this time. The vulnerability affects only version 1.0 of the product, which is a niche hotel reservation system likely deployed in small to medium hospitality businesses. The lack of supply chain or third-party integrations reduces the broader systemic risk, but the direct impact on affected systems can be significant due to the critical nature of database integrity in reservation management systems.

For European organizations, particularly those in the hospitality sector using the Simple Online Hotel Reservation System version 1.0, this vulnerability poses a risk of unauthorized data access and manipulation. Exploitation could lead to exposure of customer personal data, booking details, and potentially payment information if stored in the same database. This compromises confidentiality and could result in regulatory non-compliance under GDPR, leading to legal and financial penalties. Integrity of booking data may be compromised, causing operational disruptions such as double bookings or incorrect room availability, impacting customer trust and revenue. Availability impact is likely limited but possible if attackers execute destructive SQL commands. Since the vulnerability is remotely exploitable without authentication, attackers can target exposed administrative interfaces directly, increasing risk. European hospitality businesses often rely on such systems for daily operations, so even medium-severity vulnerabilities can have outsized operational and reputational consequences. The lack of known active exploitation reduces immediate risk but the public disclosure of the exploit code increases the likelihood of opportunistic attacks.

1. Immediate mitigation should include restricting access to the /admin/add_room.php endpoint by IP whitelisting or VPN access to limit exposure to trusted personnel only. 2. Implement Web Application Firewall (WAF) rules specifically designed to detect and block SQL injection attempts targeting the 'room_type' parameter. 3. Apply input validation and parameterized queries or prepared statements in the application code to sanitize and safely handle user inputs, eliminating injection vectors. Since no official patch is currently available, organizations should consider code review and manual patching of the vulnerable parameter handling. 4. Conduct thorough database and application logs monitoring for suspicious queries or anomalies indicative of exploitation attempts. 5. If feasible, isolate the affected system from critical networks until a secure version or patch is applied. 6. Engage with the vendor or community for updates or patches, and plan for an upgrade or migration to a more secure reservation system if the vendor does not provide timely remediation. 7. Educate administrative users on the risks and encourage strong credential policies to reduce the impact of potential lateral attacks following exploitation.