CVE-2018-25203: Online Store System CMS SQLi Vulnerability

CVE-2018-25203 Overview

Online Store System CMS 1.0 contains a critical SQL injection vulnerability that allows unauthenticated attackers to manipulate database queries by injecting SQL code through the email parameter. Attackers can send POST requests to index.php with the action=clientaccess parameter using boolean-based blind or time-based blind SQL injection payloads in the email field to extract sensitive database information.

Critical Impact

Unauthenticated remote attackers can exploit this SQL injection vulnerability to extract sensitive data from the database, potentially compromising user credentials, customer information, and administrative access to the entire e-commerce platform.

Affected Products

• Online Store System CMS 1.0
• PHP/MySQL-based deployments of Online Store System

Discovery Timeline

• 2026-03-26 - CVE-2018-25203 published to NVD
• 2026-03-26 - Last updated in NVD database

Technical Details for CVE-2018-25203

Vulnerability Analysis

This SQL injection vulnerability (CWE-89) exists in the client access functionality of Online Store System CMS 1.0. The application fails to properly sanitize user-supplied input in the email parameter before incorporating it into SQL queries. This allows attackers to inject malicious SQL code that gets executed directly against the backend database.

The vulnerability is particularly dangerous because it requires no authentication to exploit. An attacker can craft malicious POST requests targeting the index.php endpoint with the action=clientaccess parameter, embedding SQL injection payloads within the email field. The vulnerability supports both boolean-based blind and time-based blind SQL injection techniques, enabling attackers to systematically extract database contents even when direct query results are not displayed.

Root Cause

The root cause of this vulnerability is improper input validation and the lack of parameterized queries in the application's database access layer. The email parameter from user input is directly concatenated into SQL query strings without proper escaping or the use of prepared statements. This classic SQL injection pattern allows arbitrary SQL commands to be interpreted and executed by the database server.

Attack Vector

The attack is conducted over the network without requiring any authentication or user interaction. An attacker sends specially crafted POST requests to the vulnerable index.php endpoint. The action=clientaccess parameter triggers the vulnerable code path, and the malicious SQL payload is injected via the email field. Using boolean-based blind techniques, attackers can infer data by observing different application responses, while time-based blind techniques rely on database sleep functions to exfiltrate data character by character.

The vulnerability mechanism involves submitting POST requests to index.php with an action=clientaccess parameter. The email field accepts SQL injection payloads that manipulate the underlying query logic. Attackers can use payloads that cause conditional delays (time-based) or trigger different response behaviors (boolean-based) to extract database information. For detailed technical exploitation examples, refer to the Exploit-DB #44719 entry.

Detection Methods for CVE-2018-25203

Indicators of Compromise

• Unusual POST requests to index.php with action=clientaccess parameter containing SQL syntax patterns in the email field
• Database logs showing queries with SQL injection signatures such as SLEEP(), WAITFOR, BENCHMARK(), or boolean logic operators
• Abnormal response times on the client access endpoint indicating time-based blind SQL injection attempts
• Error logs revealing SQL syntax errors or database exception messages

Detection Strategies

• Deploy Web Application Firewall (WAF) rules to detect and block SQL injection patterns in POST parameters, particularly targeting the email field
• Implement intrusion detection system (IDS) signatures for common SQL injection payloads including UNION SELECT, OR 1=1, and time-based functions
• Monitor application logs for repeated requests to index.php?action=clientaccess with varying email parameter values
• Configure database audit logging to alert on suspicious query patterns or unauthorized data access attempts

Monitoring Recommendations

• Enable detailed logging for all requests to authentication and client access endpoints
• Set up alerting for database queries with abnormal execution times that may indicate time-based blind injection
• Monitor for bulk data exfiltration patterns from customer or user tables
• Implement rate limiting on the client access functionality to slow down automated injection attacks

How to Mitigate CVE-2018-25203

Immediate Actions Required

• Take the vulnerable Online Store System CMS installation offline or restrict access while implementing fixes
• Implement parameterized queries or prepared statements for all database operations involving user input
• Deploy a Web Application Firewall with SQL injection protection rules in front of the application
• Review database access logs to determine if the vulnerability has been exploited and assess potential data breach scope

Patch Information

No official vendor patch has been identified for this vulnerability. As Online Store System CMS 1.0 appears to be an unsupported or abandoned application, organizations should consider migrating to an actively maintained e-commerce platform. For technical details and proof-of-concept information, refer to the VulnCheck Advisory and Exploit-DB #44719.

Workarounds

• Implement input validation to reject email addresses containing SQL metacharacters such as single quotes, semicolons, and SQL keywords
• Use a Web Application Firewall (WAF) to filter malicious SQL injection payloads before they reach the application
• Restrict database user permissions to the minimum required privileges, limiting potential damage from successful exploitation
• Consider replacing the vulnerable application with a supported e-commerce solution that follows secure coding practices

Remediation involves modifying the vulnerable code to use prepared statements with bound parameters. Ensure all user input is treated as data, not as part of the SQL command structure. Input validation should be implemented as a defense-in-depth measure but should not be relied upon as the primary protection against SQL injection.