CVE-2025-6749 is a critical SQL Injection vulnerability identified in the huija bicycleSharingServer product, specifically affecting the function searchAdminMessageShow within the AdminController.java file. The vulnerability arises from improper sanitization or validation of the 'Title' argument, which is directly used in SQL queries. This flaw allows an unauthenticated remote attacker to inject malicious SQL code, potentially manipulating the backend database. The vulnerability does not require user interaction and can be exploited remotely without authentication, increasing its risk profile. The product does not use versioning, complicating the identification of affected or unaffected releases beyond the known affected commit hash (7b8a3ba48ad618604abd4797d2e7cf3b5ac7625a). Although the CVSS 4.0 base score is 5.3 (medium severity), the ability to perform SQL Injection remotely without authentication typically elevates the risk, as it can lead to unauthorized data access, data modification, or denial of service. No public exploits are currently known in the wild, but the exploit details have been disclosed publicly, increasing the likelihood of future exploitation. The vulnerability impacts the confidentiality, integrity, and availability of the system, as attackers could extract sensitive data, alter records, or disrupt service operations. The lack of patch information indicates that mitigation may require custom code review and remediation by the vendor or users of the software. Organizations using huija bicycleSharingServer should prioritize identifying affected deployments and applying input validation and parameterized queries to eliminate the injection vector.

For European organizations, this vulnerability poses significant risks, especially for entities operating or managing bicycle sharing services using the huija bicycleSharingServer platform. Exploitation could lead to unauthorized access to administrative messages or other sensitive data, potentially exposing user information or operational details. This could damage customer trust, lead to regulatory non-compliance under GDPR due to data breaches, and disrupt critical urban mobility services. The attack's remote and unauthenticated nature means attackers can operate from anywhere, increasing the threat surface. Additionally, if attackers manipulate administrative functions, they could degrade service availability or integrity, impacting public transportation infrastructure reliability. Given the increasing reliance on smart city and shared mobility solutions in Europe, this vulnerability could have cascading effects on urban transport ecosystems and associated services.

Specific mitigation steps include: 1) Immediate code audit of the AdminController.java, focusing on the searchAdminMessageShow function to identify and sanitize all inputs, especially the 'Title' parameter. 2) Implement parameterized queries or prepared statements to prevent SQL Injection. 3) Employ input validation and sanitization libraries to enforce strict data formats and reject malicious input. 4) Restrict database user privileges to the minimum necessary to limit potential damage from injection attacks. 5) Monitor logs for suspicious query patterns or repeated failed attempts targeting the 'Title' parameter. 6) If vendor patches become available, apply them promptly. 7) Consider deploying Web Application Firewalls (WAFs) with rules targeting SQL Injection patterns as an interim protective measure. 8) Conduct penetration testing focused on injection vectors to verify the effectiveness of mitigations. 9) Establish incident response procedures to quickly address any detected exploitation attempts.