An unauthenticated SQL injection vulnerability in SourceCodester Online Voting System version 1.0 allows remote attackers to manipulate database queries and potentially compromise system data.

The application fails to properly sanitize the username parameter within the /ajax.php?action=login file, which is processed directly in SQL queries. This allows an unauthenticated attacker to inject malicious SQL commands to bypass authentication or extract sensitive database information.

Successful exploitation of this vulnerability can lead to unauthorized access to the underlying database, resulting in the leakage of sensitive user information or voting records. Given the CVSS score of 7.3, this represents a high risk to data integrity and confidentiality, potentially leading to a complete compromise of the voting application and loss of trust in the system.

Immediate Action: As no official patch is currently available, administrators should restrict access to the login interface or implement strict input validation on the username field at the application level.

Proactive Monitoring: Review web server access logs for anomalous traffic directed at /ajax.php, specifically monitoring for unusual characters or SQL syntax patterns within the POST parameters.

Compensating Controls: Deploy a Web Application Firewall (WAF) with rules configured to detect and block common SQL injection patterns targeting the login endpoint.

Public Exploit Available: Yes — a published proof-of-concept exists as detailed in the technical write-up on GitHub.

Due to the high severity and the availability of a public proof-of-concept, users are urged to treat this vulnerability with urgency. If the application cannot be secured via code changes or WAF rules, it should be taken offline until a vendor-supplied update or secure configuration is available to prevent unauthorized database access.