An unauthenticated SQL injection vulnerability in PHPGurukul Daily Expense Tracking System 1.1 poses a significant risk of unauthorized database interaction.

This vulnerability is a SQL injection (CWE-89) located in the register.php file. Unauthenticated attackers can inject malicious SQL commands via the email parameter to interact with the backend database.

The CVSS score of 7.3 classifies this as a high-severity vulnerability due to the ease of remote exploitation. Successful exploitation could lead to unauthorized data exposure, potential modification of application data, or disruption of database services, resulting in significant reputational and operational impact.

Immediate Action: As no official patch is currently available, users should restrict access to the registration page or implement strict input validation to sanitize the email parameter before it is processed by the database.

Proactive Monitoring: Security teams should monitor web server and database logs for anomalous queries containing SQL syntax, particularly those directed at the register.php endpoint.

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

Public Exploit Available: Yes — a published proof-of-concept exists and is documented in the referenced GitHub issue.

Given the availability of a public proof-of-concept and the lack of an official vendor patch, this vulnerability presents a tangible risk to any organization running the affected software. Administrators must prioritize isolating the affected component and implementing robust input filtering to prevent exploitation until the vendor releases a secure update.