An unauthenticated remote SQL injection vulnerability exists in SourceCodester Simple and Nice Shopping Cart Script 1.0, posing a significant risk of unauthorized database access and data compromise.

The application fails to properly sanitize the username parameter within the /signup.php file before using it in SQL queries. This allows an unauthenticated attacker to inject malicious SQL commands, enabling unauthorized database manipulation and information disclosure.

Successful exploitation of this vulnerability allows an attacker to bypass security controls to read, modify, or delete sensitive information from the underlying database. Given the CVSS score of 7.3, this flaw represents a high-severity risk that could lead to complete loss of data confidentiality and integrity, potentially resulting in severe reputational damage and regulatory non-compliance.

Immediate Action: As no official vendor patch is currently available, administrators should immediately restrict access to the /signup.php endpoint or take the application offline until a secure version is released.

Proactive Monitoring: Review web server access logs for suspicious POST requests to /signup.php containing SQL syntax characters such as single quotes, semicolons, or sleep commands.

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

Public Exploit Available: Yes, a published proof-of-concept exists via the researcher's GitHub issue report.

This vulnerability presents a high risk to organizational data security due to the ease of exploitation and the availability of public proof-of-concept code. IT teams must prioritize the immediate implementation of compensating controls or service suspension to prevent unauthorized database access while awaiting a definitive vendor fix.