CVE-2025-8251: Exam Form Submission SQL Injection Flaw

CVE-2025-8251 Overview

A critical SQL injection vulnerability has been identified in code-projects Exam Form Submission version 1.0. The vulnerability exists in an unknown functionality of the file /admin/delete_s4.php, where improper handling of the ID argument allows attackers to inject malicious SQL queries. This flaw can be exploited remotely without authentication, potentially enabling unauthorized access to sensitive database information, data manipulation, or complete database compromise.

Critical Impact
Remote attackers can exploit this SQL injection vulnerability to read, modify, or delete data in the backend database, potentially compromising the entire exam form submission system and exposing student or administrative data.

Affected Products

code-projects Exam Form Submission 1.0

Discovery Timeline

July 28, 2025 - CVE-2025-8251 published to NVD
July 30, 2025 - Last updated in NVD database

Technical Details for CVE-2025-8251

Vulnerability Analysis

This SQL injection vulnerability affects the administrative deletion functionality within the Exam Form Submission application. The vulnerable endpoint /admin/delete_s4.php accepts an ID parameter that is incorporated directly into SQL queries without proper sanitization or parameterization. The flaw is classified under CWE-74 (Improper Neutralization of Special Elements in Output Used by a Downstream Component), which encompasses injection vulnerabilities where user-controlled input is embedded into commands or queries.

The vulnerability allows attackers to manipulate the database layer of the application, potentially extracting sensitive information such as student records, exam submissions, and administrative credentials stored in the database.

Root Cause

The root cause of this vulnerability is the failure to properly validate, sanitize, or parameterize user-supplied input before incorporating it into SQL queries. The ID parameter passed to /admin/delete_s4.php is directly concatenated into a SQL statement, allowing attackers to inject arbitrary SQL commands. This represents a fundamental failure to implement secure coding practices such as prepared statements or parameterized queries.

Attack Vector

The attack can be launched remotely over the network without requiring prior authentication. An attacker crafts a malicious HTTP request to the /admin/delete_s4.php endpoint, embedding SQL injection payloads within the ID parameter. When the server processes this request, the injected SQL code executes against the backend database.

The exploitation technique involves manipulating the ID parameter with SQL syntax such as single quotes, UNION statements, or boolean-based injection payloads. Successful exploitation can lead to unauthorized data extraction, authentication bypass, or database modification. The exploit has been publicly disclosed, as detailed in the GitHub Issue CVE-ZhuChengQing.

Detection Methods for CVE-2025-8251

Indicators of Compromise

Unusual SQL error messages in application logs containing syntax errors or unexpected query patterns
HTTP requests to /admin/delete_s4.php containing SQL keywords such as UNION, SELECT, OR 1=1, or comment sequences (--, /**/)
Unexpected database query activity or data exfiltration patterns
Multiple failed or anomalous requests targeting the ID parameter with encoded or obfuscated payloads

Detection Strategies

Implement Web Application Firewall (WAF) rules to detect and block common SQL injection patterns in the ID parameter
Monitor web server access logs for requests to /admin/delete_s4.php with suspicious query strings containing SQL metacharacters
Deploy database activity monitoring to detect anomalous queries originating from the application
Configure intrusion detection systems (IDS) with signatures for SQL injection attack patterns

Monitoring Recommendations

Enable verbose logging on the web server and database to capture detailed request and query information
Implement real-time alerting for any requests containing potential SQL injection indicators targeting administrative endpoints
Regularly review access logs for patterns indicating automated vulnerability scanning or exploitation attempts
Monitor for unusual database account activity or privilege escalation attempts

How to Mitigate CVE-2025-8251

Immediate Actions Required

Restrict access to the /admin/delete_s4.php endpoint through network segmentation or IP whitelisting until a patch is available
Implement input validation and WAF rules to filter malicious SQL injection payloads
Review and audit other endpoints in the application for similar injection vulnerabilities
Consider taking the affected functionality offline if exploitation risk is deemed critical

Patch Information

No official vendor patch has been released at the time of publication. Organizations should monitor the Code Projects website for security updates. Additional technical details regarding this vulnerability are available through VulDB #317839.

Workarounds

Implement prepared statements or parameterized queries in the vulnerable PHP code to prevent SQL injection
Deploy a Web Application Firewall with SQL injection protection rules in front of the application
Restrict administrative endpoint access to trusted IP addresses only using server-level access controls
Add input validation to ensure the ID parameter only accepts numeric values

bash

# Example: Apache configuration to restrict access to admin endpoints
<Directory "/var/www/html/admin">
    Require ip 192.168.1.0/24
    Require ip 10.0.0.0/8
</Directory>