CVE-2026-3746: Simple Responsive Tourism Website SQLi Flaw

CVE-2026-3746 Overview

A SQL injection vulnerability has been identified in SourceCodester Simple Responsive Tourism Website version 1.0. This vulnerability exists in the Login component, specifically within the file /tourism/classes/Login.php?f=login. An attacker can exploit this flaw by manipulating the Username argument, allowing for unauthorized SQL query injection. The attack can be initiated remotely without authentication, and exploit information has been publicly disclosed.

Critical Impact

Unauthenticated remote attackers can exploit this SQL injection vulnerability to bypass authentication, extract sensitive database information, modify or delete data, and potentially gain unauthorized access to the underlying system.

Affected Products

• SourceCodester Simple Responsive Tourism Website 1.0
• oretnom23 simple_responsive_tourism_website

Discovery Timeline

• 2026-03-08 - CVE-2026-3746 published to NVD
• 2026-03-09 - Last updated in NVD database

Technical Details for CVE-2026-3746

Vulnerability Analysis

This vulnerability is classified as CWE-74 (Improper Neutralization of Special Elements in Output Used by a Downstream Component), commonly manifesting as an injection flaw. The Login component in the Simple Responsive Tourism Website fails to properly sanitize user-supplied input in the Username parameter before incorporating it into SQL queries. This allows attackers to inject arbitrary SQL commands that are executed by the database engine.

The network-accessible nature of this vulnerability means it can be exploited remotely by any attacker who can reach the login endpoint. No authentication or user interaction is required to exploit this flaw, making it particularly dangerous for publicly exposed installations.

Root Cause

The root cause of this vulnerability is inadequate input validation and sanitization in the Login.php file. The application directly incorporates user-controlled input from the Username field into SQL queries without proper parameterization or escaping. This classic SQL injection pattern occurs when developers construct SQL statements through string concatenation rather than using prepared statements with parameterized queries.

Attack Vector

The attack vector is network-based, targeting the login functionality at /tourism/classes/Login.php?f=login. An attacker can craft malicious payloads in the Username parameter to:

1. Bypass authentication by injecting SQL logic that always evaluates to true
2. Extract sensitive data from the database using UNION-based or error-based injection techniques
3. Enumerate database schema and table structures
4. Modify or delete database records if the database user has sufficient privileges
5. Potentially execute operating system commands if database features like xp_cmdshell (MSSQL) or LOAD_FILE (MySQL) are available

The vulnerability allows attackers to manipulate the Username argument to inject arbitrary SQL syntax. When the application processes the login request, the unsanitized input is directly concatenated into the SQL query, allowing the injected code to be executed. For detailed technical information about the exploit mechanism, refer to the vulnerability report on GitHub.

Detection Methods for CVE-2026-3746

Indicators of Compromise

• Unusual SQL error messages in web server logs, particularly those referencing the /tourism/classes/Login.php endpoint
• Multiple failed login attempts with suspicious characters in usernames (e.g., single quotes, double dashes, UNION keywords)
• Unexpected database queries or data access patterns originating from the web application
• Authentication bypass events where users gain access without valid credentials

Detection Strategies

• Deploy Web Application Firewall (WAF) rules to detect and block common SQL injection patterns in the Username parameter
• Monitor application logs for SQL syntax errors or database exceptions triggered during login attempts
• Implement intrusion detection system (IDS) signatures targeting SQL injection payloads in HTTP POST requests to the login endpoint
• Review database audit logs for unusual queries, unauthorized data access, or privilege escalation attempts

Monitoring Recommendations

• Enable detailed logging on the web server to capture all requests to /tourism/classes/Login.php
• Configure database query logging to identify suspicious SQL statements originating from the application
• Set up alerts for repeated authentication failures with malformed username inputs
• Monitor for unexpected outbound database connections or data exfiltration attempts

How to Mitigate CVE-2026-3746

Immediate Actions Required

• Remove or restrict public access to SourceCodester Simple Responsive Tourism Website installations until patched
• Implement input validation and sanitization for the Username parameter at the application or WAF level
• Review database user privileges and apply the principle of least privilege to limit potential damage from exploitation
• Audit existing database records for signs of unauthorized access or data manipulation

Patch Information

As of the last update on 2026-03-09, no official patch has been released by the vendor. Organizations using this software should monitor the SourceCodester website for security updates. Additionally, technical details and vulnerability reports are available through VulDB and the GitHub vulnerability report.

Workarounds

• Implement a Web Application Firewall (WAF) with SQL injection detection rules to filter malicious requests
• Manually modify the Login.php file to use prepared statements with parameterized queries instead of string concatenation
• Restrict access to the application using IP whitelisting or VPN requirements to limit exposure
• Disable the vulnerable login endpoint if alternative authentication mechanisms are available

# Example Apache configuration to restrict access to the vulnerable endpoint
<Location "/tourism/classes/Login.php">
    # Restrict access to trusted IP addresses only
    Require ip 192.168.1.0/24
    Require ip 10.0.0.0/8
</Location>