CVE-2025-4456: Car Rental Project SQL Injection Flaw

CVE-2025-4456 Overview

A critical SQL Injection vulnerability has been identified in Project Worlds Car Rental Project version 1.0. The vulnerability exists in the /signup.php file, where improper handling of the fname parameter allows attackers to inject malicious SQL commands. This flaw enables remote attackers to manipulate database queries without authentication, potentially leading to unauthorized data access, data modification, or complete database compromise.

Critical Impact

Remote attackers can exploit this SQL Injection vulnerability to bypass authentication, extract sensitive user data, modify database records, or potentially gain further system access through database functions.

Affected Products

• Project Worlds Car Rental Project 1.0
• Installations with exposed /signup.php endpoint
• Other parameters in the signup form may also be affected

Discovery Timeline

• 2025-05-09 - CVE-2025-4456 published to NVD
• 2025-07-11 - Last updated in NVD database

Technical Details for CVE-2025-4456

Vulnerability Analysis

This SQL Injection vulnerability stems from insufficient input validation in the user registration functionality of the Car Rental Project application. The /signup.php endpoint fails to properly sanitize the fname (first name) parameter before incorporating it into SQL queries. When user-supplied input is directly concatenated into database queries without proper escaping or parameterization, attackers can inject arbitrary SQL syntax that alters the intended query logic.

The vulnerability is remotely exploitable without any authentication requirements, meaning any user who can access the signup page can attempt exploitation. The public disclosure of this exploit increases the risk of widespread attacks against vulnerable installations. According to the CVE description, other parameters in the signup form may also be susceptible to similar injection attacks.

Root Cause

The root cause of this vulnerability is the failure to implement proper input validation and parameterized queries (prepared statements) when processing user-supplied data in the registration form. The application directly incorporates the fname parameter value into SQL query strings, creating an injection point that allows attackers to break out of the expected data context and execute arbitrary SQL commands.

This is a classic example of CWE-89 (Improper Neutralization of Special Elements used in an SQL Command) and CWE-74 (Improper Neutralization of Special Elements in Output Used by a Downstream Component). PHP applications that use direct string concatenation with mysqli or PDO functions without prepared statements are particularly susceptible to this type of vulnerability.

Attack Vector

The attack can be executed remotely over the network by submitting a crafted HTTP request to the /signup.php endpoint. An attacker would modify the fname parameter to include SQL metacharacters and malicious SQL statements. Common attack payloads include:

• Authentication Bypass: Injecting conditions that always evaluate to true
• Data Exfiltration: Using UNION-based injection to extract data from other tables
• Blind SQL Injection: Using time-based or boolean-based techniques when direct output is not available
• Database Manipulation: Inserting, updating, or deleting records in the database

The vulnerability requires no user interaction and no prior authentication, making it easily exploitable by automated scanning tools. Additional technical details can be found in the GitHub Issue Report and VulDB entry #308070.

Detection Methods for CVE-2025-4456

Indicators of Compromise

• Unusual or malformed requests to /signup.php containing SQL syntax characters such as single quotes, double dashes, semicolons, or UNION keywords
• Database error messages appearing in application logs or user-facing pages
• Unexpected database queries or anomalous query patterns in database audit logs
• Signs of data exfiltration or unauthorized access to user records

Detection Strategies

• Deploy Web Application Firewall (WAF) rules to detect and block SQL injection patterns in HTTP parameters
• Enable database query logging and monitor for suspicious query patterns including error-based, UNION-based, and time-based injection attempts
• Implement intrusion detection signatures for common SQL injection payloads targeting the fname parameter
• Analyze web server access logs for requests to /signup.php with encoded or suspicious parameter values

Monitoring Recommendations

• Configure real-time alerting for SQL syntax errors or database exceptions originating from the signup functionality
• Monitor for bulk registration attempts or automated scanning activity targeting the /signup.php endpoint
• Establish baseline metrics for normal database query volumes and alert on deviations
• Review application and database logs regularly for evidence of exploitation attempts

How to Mitigate CVE-2025-4456

Immediate Actions Required

• Remove or restrict access to the /signup.php endpoint until a patch is applied
• Implement Web Application Firewall rules to filter SQL injection payloads
• Review database logs for evidence of prior exploitation and assess potential data breach
• Consider taking the application offline if it handles sensitive user data and no fix is immediately available

Patch Information

As of the last update, no official patch has been released by Project Worlds for this vulnerability. Organizations using the Car Rental Project should check the VulDB entry and GitHub issue for the latest information on vendor response and available fixes. Users may need to implement code-level fixes manually or migrate to a more secure application.

Workarounds

• Implement input validation to reject or sanitize SQL metacharacters from all user inputs before processing
• Refactor the vulnerable code to use prepared statements with parameterized queries instead of string concatenation
• Deploy a reverse proxy or WAF with SQL injection detection rules as a compensating control
• Restrict network access to the application using IP allowlisting or VPN requirements

# Example WAF rule for ModSecurity to block SQL injection attempts
SecRule ARGS:fname "@detectSQLi" \
    "id:100001,\
    phase:2,\
    deny,\
    status:403,\
    msg:'SQL Injection attempt detected in fname parameter',\
    log,\
    auditlog"