CVE-2026-9525: SQL Injection in itsourcecode Electronic Judging System 1.0

Executive Summary

CVE-2026-9525 is a SQL injection vulnerability in itsourcecode Electronic Judging System version 1.0, affecting the /admin/edit_judge.php endpoint. The flaw allows remote attackers to manipulate database queries by injecting malicious SQL through the judge_id parameter. The exploit has been publicly disclosed and proof-of-concept code is available.

CVSS Score: 7.3 (High)

Vulnerability Details

Root Cause

The vulnerability exists in the admin panel's judge editing functionality. The application constructs a SQL query using the judge_id parameter without proper sanitization or parameterized queries, enabling classic SQL injection.

When a user submits an HTTP request to /admin/edit_judge.php, the judge_id value is directly interpolated into a SQL query:

// Vulnerable pattern (illustrative)
$query = "SELECT * FROM judges WHERE id = " . $_GET['judge_id'];

An attacker can append SQL metacharacters and statements to alter query logic, extract data, or — depending on database permissions — execute operating system commands.

Attack Vectors

Potential Impact

A successful SQL injection attack against this endpoint could allow an attacker to:

• Extract sensitive data — judge credentials, competition results, participant information stored in the database
• Bypass authentication — manipulate login queries to gain admin access without valid credentials
• Modify or delete data — alter competition records, rankings, or system configuration
• Database enumeration — map the full schema for further attacks
• OS command execution — if the database user has FILE or EXECUTE privileges, escalate to server-level access via LOAD_FILE, INTO OUTFILE, or stored procedures

Affected Versions

Remediation

Immediate Actions

1. Apply vendor patch — check itsourcecode's repository for an updated version addressing this vulnerability
2. Restrict admin panel access — place /admin/ behind IP allowlisting or VPN requirement to limit attack surface
3. Review database user privileges — ensure the application database account has minimal necessary permissions (SELECT/INSERT/UPDATE only, no FILE or OS-level privileges)
4. Enable WAF rules — deploy or update Web Application Firewall rules to detect and block SQL injection attempts targeting this endpoint

Developer Remediation

Replace direct string interpolation with parameterized queries or prepared statements:

// Secure pattern using PDO prepared statements
$stmt = $pdo->prepare("SELECT * FROM judges WHERE id = :judge_id");
$stmt->execute([':judge_id' => $_GET['judge_id']]);
$result = $stmt->fetchAll();

All user-supplied input that interacts with database queries must go through prepared statements or equivalent ORM abstraction layers.

Input Validation

Even with parameterized queries in place, validate and sanitize inputs at the application boundary:

// Validate judge_id is a positive integer before use
$judge_id = filter_var($_GET['judge_id'], FILTER_VALIDATE_INT);
if ($judge_id === false || $judge_id <= 0) {
    http_response_code(400);
    exit('Invalid judge ID');
}

Detection

Web Server Log Analysis

Look for anomalous edit_judge.php requests containing SQL metacharacters:

# Grep for SQL injection indicators in access logs
grep "edit_judge.php" /var/log/apache2/access.log | \
  grep -iE "(%27|'|%22|\"|union|select|--|\;|0x)"
 
# Detect encoded injection attempts
grep "edit_judge.php" /var/log/nginx/access.log | \
  grep -iE "(union.*select|or.*1.*=.*1|drop.*table|information_schema)"

Database Query Monitoring

Enable MySQL general query logging temporarily to audit queries against the judges table:

-- Enable query logging
SET GLOBAL general_log = 'ON';
SET GLOBAL general_log_file = '/var/log/mysql/general.log';
 
-- Monitor for suspicious patterns
SELECT * FROM mysql.general_log
WHERE argument LIKE '%UNION%SELECT%'
   OR argument LIKE '%information_schema%'
ORDER BY event_time DESC
LIMIT 50;

Timeline

References

• NVD — CVE-2026-9525
• OWASP SQL Injection Prevention Cheat Sheet