CVE-2026-0733: PHPGurukul Course System SQLi Vulnerability

CVE-2026-0733 Overview

A SQL injection vulnerability has been identified in PHPGurukul Online Course Registration System up to version 3.1. The vulnerability exists in the /onlinecourse/admin/manage-students.php file, where improper handling of the cid argument allows attackers to inject malicious SQL queries. This flaw can be exploited remotely by authenticated attackers with low privileges, potentially enabling unauthorized access to sensitive database information, data manipulation, or further system compromise.

Critical Impact

Remote attackers can exploit this SQL injection vulnerability to extract sensitive data, modify database records, or potentially escalate their access within the affected system. The exploit has been publicly disclosed and may be actively utilized.

Affected Products

• PHPGurukul Online Course Registration System versions up to 3.1
• Systems running vulnerable /onlinecourse/admin/manage-students.php endpoint

Discovery Timeline

• 2026-01-09 - CVE-2026-0733 published to NVD
• 2026-01-09 - Last updated in NVD database

Technical Details for CVE-2026-0733

Vulnerability Analysis

This SQL injection vulnerability (CWE-74: Improper Neutralization of Special Elements in Output Used by a Downstream Component) affects the administrative student management functionality within PHPGurukul Online Course Registration System. The vulnerable endpoint processes the cid parameter without proper sanitization, allowing malicious SQL statements to be injected into database queries.

The vulnerability is accessible over the network and requires low-privilege authentication to exploit. Upon successful exploitation, an attacker can achieve unauthorized read and write access to the underlying database, potentially compromising student records, course information, and administrative credentials stored within the system.

Root Cause

The root cause of this vulnerability is the failure to properly sanitize user-supplied input in the cid parameter before incorporating it into SQL queries. The manage-students.php script directly concatenates or interpolates the cid value into database queries without using parameterized queries or prepared statements, allowing attackers to manipulate query logic.

Attack Vector

The attack is network-based, targeting the /onlinecourse/admin/manage-students.php endpoint. An authenticated attacker with low-level privileges can craft malicious requests containing SQL injection payloads in the cid parameter. These payloads can modify the intended SQL query structure to extract data, bypass authorization checks, or manipulate database records.

The exploitation involves sending crafted HTTP requests to the vulnerable endpoint with specially formatted cid parameter values containing SQL metacharacters and commands. For detailed technical analysis, refer to the HXLab Shared Resource and VulDB #340130.

Detection Methods for CVE-2026-0733

Indicators of Compromise

• Unusual SQL error messages in application logs referencing manage-students.php
• Abnormal HTTP requests to /onlinecourse/admin/manage-students.php with suspicious cid parameter values containing SQL syntax (quotes, UNION, SELECT, etc.)
• Database logs showing unexpected queries or unauthorized data access patterns
• Anomalous authentication or session activity following requests to the vulnerable endpoint

Detection Strategies

• Implement Web Application Firewall (WAF) rules to detect and block SQL injection patterns in the cid parameter
• Monitor access logs for requests to manage-students.php containing common SQL injection keywords (UNION, SELECT, OR, AND, --, #)
• Deploy database activity monitoring to identify unusual query patterns or unauthorized data extraction attempts
• Configure intrusion detection systems (IDS) with signatures for SQL injection attack patterns

Monitoring Recommendations

• Enable verbose logging for the PHPGurukul application and associated database server
• Set up alerts for multiple failed or malformed requests to administrative endpoints
• Regularly review database audit logs for signs of data exfiltration or manipulation
• Monitor for increased traffic volume or suspicious patterns targeting the /onlinecourse/admin/ directory

How to Mitigate CVE-2026-0733

Immediate Actions Required

• Restrict access to the /onlinecourse/admin/ directory to trusted IP addresses only
• Implement input validation and sanitization for the cid parameter
• Deploy a Web Application Firewall (WAF) with SQL injection protection rules
• Review user access and remove unnecessary administrative accounts
• Consider temporarily disabling the affected functionality until a patch is applied

Patch Information

As of the last NVD update on 2026-01-09, no official vendor patch has been released. System administrators should monitor the PHP Gurukul Security Hub for security updates and apply patches immediately when available. For additional vulnerability tracking information, see VulDB CTI ID #340130.

Workarounds

• Implement prepared statements or parameterized queries in the manage-students.php file to prevent SQL injection
• Use input validation to restrict cid parameter to numeric values only
• Employ a WAF rule to filter requests containing SQL injection patterns
• Limit database user privileges to minimum required permissions for the application

# Example: Apache .htaccess to restrict admin access by IP
<Directory "/var/www/html/onlinecourse/admin">
    Order Deny,Allow
    Deny from all
    Allow from 192.168.1.0/24
    Allow from 10.0.0.0/8
</Directory>