CVE-2025-6456 is a SQL Injection vulnerability identified in version 1.0 of the code-projects Online Hotel Reservation System, specifically within the /reservation/order.php file. The vulnerability arises from improper sanitization or validation of the 'Start' parameter, which an attacker can manipulate to inject malicious SQL code. This injection flaw allows remote attackers to execute arbitrary SQL commands on the backend database without requiring authentication or user interaction. The vulnerability has been publicly disclosed, increasing the risk of exploitation, although no known exploits have been observed in the wild to date. The CVSS 4.0 base score is 6.9 (medium severity), reflecting the network attack vector, low attack complexity, no privileges or user interaction needed, but limited impact on confidentiality, integrity, and availability. The vulnerability could enable attackers to extract sensitive reservation data, modify booking records, or disrupt database operations, potentially compromising the integrity and availability of the reservation system. The lack of a patch or vendor mitigation at this time increases exposure for affected deployments. Given the critical nature of reservation systems in hospitality operations, exploitation could lead to operational disruptions, data breaches, and reputational damage.

For European organizations, particularly those in the hospitality sector using the affected Online Hotel Reservation System version 1.0, this vulnerability poses a significant risk. Successful exploitation could lead to unauthorized access to customer booking data, including personal and payment information, violating GDPR requirements and resulting in regulatory penalties. Data integrity could be compromised by altering reservation details, causing operational confusion and customer dissatisfaction. Availability impacts could disrupt booking services, leading to revenue loss and damage to brand reputation. Since the vulnerability can be exploited remotely without authentication, attackers can target systems over the internet, increasing the attack surface. European hotels and travel agencies relying on this software may face increased risk of targeted attacks, especially those with high volumes of online bookings. The public disclosure of the vulnerability further elevates the threat level, as attackers may develop and deploy automated exploit tools. Additionally, given the strategic importance of tourism in many European economies, disruption of hotel reservation systems could have broader economic implications.

1. Immediate mitigation should focus on implementing input validation and parameterized queries or prepared statements in the /reservation/order.php file to prevent SQL injection via the 'Start' parameter. 2. If source code modification is not immediately feasible, deploying a Web Application Firewall (WAF) with custom rules to detect and block SQL injection patterns targeting the 'Start' parameter can provide temporary protection. 3. Conduct a comprehensive code review of the entire reservation system to identify and remediate other potential injection points. 4. Monitor web server and database logs for suspicious queries or anomalous access patterns related to the reservation endpoint. 5. Restrict database user permissions to the minimum necessary to limit the impact of any successful injection. 6. Engage with the vendor or community maintaining the Online Hotel Reservation System to obtain or request an official patch or update. 7. For organizations unable to patch immediately, consider isolating the affected system behind VPNs or internal networks to reduce exposure. 8. Educate IT and security teams about this vulnerability and ensure incident response plans include procedures for SQL injection attacks. 9. Regularly back up reservation data and test restoration procedures to mitigate potential data loss or corruption.