CVE-2026-4780: Sales and Inventory System SQLi Vulnerability

CVE-2026-4780 Overview

A SQL injection vulnerability has been identified in SourceCodester Sales and Inventory System version 1.0. The vulnerability exists in the update_out_standing.php file within the HTTP GET Parameter Handler component. By manipulating the sid parameter, an attacker can inject malicious SQL commands that are executed by the underlying database. This attack can be carried out remotely, and a public exploit is available.

Critical Impact

Remote attackers can exploit this SQL injection vulnerability to access, modify, or delete database records, potentially compromising sensitive sales and inventory data. Public exploit availability increases the risk of active exploitation.

Affected Products

• SourceCodester Sales and Inventory System 1.0
• update_out_standing.php component
• HTTP GET Parameter Handler functionality

Discovery Timeline

• 2026-03-25 - CVE-2026-4780 published to NVD
• 2026-03-25 - Last updated in NVD database

Technical Details for CVE-2026-4780

Vulnerability Analysis

This SQL injection vulnerability (CWE-74: Improper Neutralization of Special Elements in Output Used by a Downstream Component) occurs due to insufficient input validation in the update_out_standing.php file. The sid parameter, which is received via HTTP GET requests, is not properly sanitized before being incorporated into SQL queries.

The vulnerability allows authenticated remote attackers to inject arbitrary SQL commands through the vulnerable parameter. Successful exploitation could lead to unauthorized data access, modification, or deletion of records within the application's database. Given the nature of a Sales and Inventory System, this could expose sensitive business data including transaction records, customer information, and inventory details.

Root Cause

The root cause of this vulnerability is improper input validation and a lack of parameterized queries in the update_out_standing.php file. The application directly concatenates user-supplied input from the sid GET parameter into SQL queries without proper sanitization or use of prepared statements. This allows attackers to break out of the intended query structure and inject malicious SQL commands.

Attack Vector

The attack is network-based and requires low privileges to execute. An attacker can craft a malicious URL containing SQL injection payloads in the sid parameter. When a request is made to the update_out_standing.php endpoint with the manipulated parameter, the injected SQL commands are executed against the database.

The exploitation mechanism involves sending specially crafted HTTP GET requests to the vulnerable endpoint. The attacker modifies the sid parameter value to include SQL metacharacters and commands that alter the intended query logic. For detailed technical information about the exploitation technique, refer to the GitHub PoC Repository.

Detection Methods for CVE-2026-4780

Indicators of Compromise

• Unusual SQL syntax errors in application or web server logs
• Anomalous HTTP GET requests to update_out_standing.php containing SQL metacharacters in the sid parameter
• Database query logs showing unexpected UNION SELECT, ORDER BY, or other SQL injection patterns
• Unexpected database access patterns or data exfiltration attempts

Detection Strategies

• Deploy web application firewalls (WAF) with SQL injection detection rules targeting the sid parameter
• Implement application-level logging for all requests to update_out_standing.php and monitor for suspicious patterns
• Configure database activity monitoring to alert on unusual query structures or error conditions
• Use SentinelOne Singularity to detect and respond to exploitation attempts through behavioral analysis

Monitoring Recommendations

• Monitor HTTP access logs for requests containing common SQL injection payloads (e.g., ', --, UNION, SELECT)
• Set up alerts for repeated 500-series errors from the update_out_standing.php endpoint
• Review database audit logs for queries originating from the web application that contain injection signatures
• Implement network traffic analysis to identify potential data exfiltration following exploitation

How to Mitigate CVE-2026-4780

Immediate Actions Required

• Restrict network access to the vulnerable update_out_standing.php endpoint until a patch is available
• Implement web application firewall rules to block SQL injection attempts targeting the sid parameter
• Review and enhance input validation for all user-supplied parameters in the application
• Consider disabling the vulnerable functionality if it is not critical to business operations

Patch Information

At the time of publication, no official patch has been released by SourceCodester. Organizations using the Sales and Inventory System 1.0 should monitor the SourceCodester website for security updates. Additional vulnerability details are available through VulDB #352798.

Workarounds

• Implement prepared statements or parameterized queries in the update_out_standing.php file to prevent SQL injection
• Add server-side input validation to sanitize the sid parameter before processing
• Deploy a WAF with strict SQL injection protection rules for the affected endpoint
• Limit database user privileges for the application to reduce the impact of successful exploitation

# Example WAF rule to block SQL injection in sid parameter (ModSecurity format)
SecRule ARGS:sid "@detectSQLi" \
    "id:1001,\
    phase:2,\
    deny,\
    status:403,\
    msg:'SQL Injection attempt detected in sid parameter',\
    log,\
    severity:2"