CVE-2025-9704 is a SQL Injection vulnerability identified in SourceCodester Water Billing System version 1.0. The flaw exists in the /viewbill.php file, specifically in the handling of the 'ID' parameter. An attacker can manipulate this parameter to inject malicious SQL code, which the system then executes without proper sanitization or parameterization. This vulnerability allows remote attackers to execute arbitrary SQL commands on the backend database without requiring authentication or user interaction. The CVSS 4.0 score is 6.9 (medium severity), reflecting the ease of exploitation (network accessible, no privileges or user interaction needed) but limited impact on confidentiality, integrity, and availability (all rated low). The vulnerability could lead to unauthorized data disclosure, data modification, or partial disruption of service, depending on the database and application context. No patches or fixes have been publicly released yet, and no known exploits are currently observed in the wild, although a proof-of-concept exploit has been made public, increasing the risk of exploitation.

For European organizations, especially municipal water utilities or service providers using SourceCodester Water Billing System 1.0, this vulnerability poses a tangible risk. Successful exploitation could expose sensitive customer billing information, including personal data and payment details, leading to privacy violations under GDPR. Data integrity could also be compromised, potentially causing billing inaccuracies or service disruptions. While the vulnerability does not require authentication, the impact is somewhat limited by the specific product usage scope. However, given the critical nature of water billing systems in public infrastructure, any disruption or data breach could undermine public trust and regulatory compliance. Additionally, attackers could leverage this vulnerability as a foothold for further network intrusion or lateral movement within an organization's IT environment.

Immediate mitigation should focus on input validation and parameterized queries within the /viewbill.php script to prevent SQL injection. Organizations should audit their SourceCodester Water Billing System installations to identify affected versions and isolate vulnerable endpoints. If patching is not yet available, applying Web Application Firewall (WAF) rules to detect and block SQL injection patterns targeting the 'ID' parameter can reduce risk. Network segmentation and strict access controls around billing systems can limit exposure. Regular database backups and monitoring for anomalous queries or access patterns are recommended. Organizations should also engage with the vendor or community for updates and patches and plan for timely application once available. Finally, conducting security awareness training for administrators to recognize exploitation signs can aid early detection.