CVE-2025-22781

Executive Summary

CVE-2025-22781 is a DOM-Based Cross-Site Scripting (XSS) vulnerability in the Nativery WordPress plugin (versions ≤ 0.1.6). The plugin fails to properly neutralize user-controlled input during web page generation, allowing an attacker to inject malicious scripts that execute in the victim's browser within the context of the WordPress site. This vulnerability is classified as a WordPress ecosystem issue and does not involve Apache or Nginx misconfigurations.

The CVSS score is 6.5 (Medium), with a low EPSS probability (0.0%), indicating limited active exploitation in the wild. No public exploit code or proof-of-concept is currently available, and no official patch has been released by the vendor. The attack vector is network-based, requires user interaction, and can lead to partial compromise of confidentiality, integrity, and availability.

Supply Chain & Package Security

This vulnerability affects a WordPress plugin distributed via the official WordPress plugin repository. Users who installed the plugin from the repository are at risk. Since no patch exists, the supply chain risk is elevated—users must either remove the plugin or apply a virtual patch via a Web Application Firewall (WAF). The plugin is not available on NPM, PyPI, Go, or Ruby ecosystems.

CVSS Breakdown & Threat Level

• Attack Vector (AV): Network (N) – Exploitable remotely.
• Attack Complexity (AC): Low (L) – No special conditions required.
• Privileges Required (PR): None (N) – No authentication needed.
• User Interaction (UI): Required (R) – Victim must click a crafted link or visit a malicious page.
• Scope (S): Changed (C) – The injected script can affect resources beyond the vulnerable component.
• Confidentiality (C): Low (L) – Limited data exposure.
• Integrity (I): Low (L) – Limited ability to modify content.
• Availability (A): Low (L) – Limited impact on service availability.

Threat Level: Medium. The vulnerability is easy to exploit but requires user interaction. No active exploitation campaigns have been observed.

Deep Dive & Mechanics

The vulnerability resides in the Nativery plugin's JavaScript code, which processes user-supplied input (e.g., URL parameters, fragment identifiers) and injects it into the DOM without proper sanitization. DOM-Based XSS occurs entirely on the client side; the server does not reflect the malicious payload. The attack flow is as follows:

1. An attacker crafts a malicious URL containing a JavaScript payload in a parameter (e.g., #<script>alert(1)</script>).
2. The victim clicks the link, which loads the WordPress page with the Nativery plugin active.
3. The plugin's JavaScript reads the fragment identifier or other DOM input and writes it directly into the page using innerHTML or similar methods.
4. The browser executes the injected script, leading to XSS.

The vulnerable code likely uses document.location.hash or document.URL without proper encoding. For example:

var userInput = window.location.hash.substring(1);
document.getElementById('nativery-container').innerHTML = userInput;

Vulnerable vs. Patched Code

Vulnerable Code (Nativery ≤ 0.1.6):

// Unsafe: directly assigns user input to innerHTML
var hash = window.location.hash;
if (hash) {
    document.getElementById('nativery-box').innerHTML = hash.substring(1);
}

Patched Code (Hypothetical):

// Safe: uses textContent to prevent HTML injection
var hash = window.location.hash;
if (hash) {
    document.getElementById('nativery-box').textContent = hash.substring(1);
}

Since no official patch exists, users must implement a virtual patch or remove the plugin.

Exploitation & Lab Setup

Red Team

Prerequisites:

• A WordPress site with Nativery plugin version ≤ 0.1.6.
• Ability to deliver a crafted URL to a victim (e.g., via phishing email).

Exploit Steps:

1. Craft a malicious URL:

   https://victim-site.com/?page_id=123#<img src=x onerror=alert('XSS')>
   

2. Send the URL to the victim.
3. When the victim clicks the link, the script executes in their browser.

Example Payload:

#<svg onload=alert(document.cookie)>

Blue Team

Detection:

• Monitor web server logs for requests containing # followed by script tags or event handlers.
• Use WAF rules to block requests with suspicious fragment identifiers.

Hunting Query (Splunk):

index=web sourcetype=access_combined uri_path="/*" uri_query="*#*" | search uri_query IN ("*<script*", "*onerror*", "*onload*")

Indicators of Compromise (IOCs)

• URL Pattern: Requests containing #<script or #<img in the fragment identifier.
• Client-Side Artifacts: JavaScript execution of alert(), document.cookie, or fetch() to external domains.
• Network Traffic: Outbound connections to attacker-controlled domains from the victim's browser.
• File Hashes (Plugin): No specific hashes available; version ≤ 0.1.6 is vulnerable.

Detection Engineering

YARA Rule

rule CVE_2025_22781_DOM_XSS {
    meta:
        description = "Detects Nativery plugin files vulnerable to DOM-Based XSS"
        author = "Valters IT"
        date = "2025-02-15"
        reference = "CVE-2025-22781"
    strings:
        $vuln_func = "innerHTML" nocase
        $hash_ref = "location.hash" nocase
        $url_ref = "document.URL" nocase
    condition:
        all of ($vuln_func, $hash_ref) or all of ($vuln_func, $url_ref)
}

Sigma Rule

title: CVE-2025-22781 DOM-Based XSS in Nativery Plugin
id: 8a3f2c1e-5d7b-4a9f-8c2e-1b3d5f7a9c0e
status: experimental
description: Detects HTTP requests with suspicious fragment identifiers targeting Nativery plugin
author: Valters IT
date: 2025-02-15
logsource:
    category: webserver
    product: apache
detection:
    selection:
        cs-uri-query|contains:
            - '#<script'
            - '#<img'
            - '#<svg'
            - '#onerror'
            - '#onload'
    condition: selection
falsepositives:
    - Legitimate use of hash fragments with similar patterns (rare)
level: high

Suricata Rule

alert http any any -> any any (msg:"CVE-2025-22781 DOM-Based XSS Attempt"; flow:to_server,established; content:"#<script"; http_uri; nocase; sid:1000001; rev:1;)
alert http any any -> any any (msg:"CVE-2025-22781 DOM-Based XSS Attempt - Event Handler"; content:"#<img"; http_uri; nocase; sid:1000002; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Remove the plugin from all WordPress installations until a patch is released.
2. Apply a virtual patch using a WAF (e.g., ModSecurity, Cloudflare) to block requests containing #<script or similar patterns in the URI.
3. Educate users not to click suspicious links, especially those with unusual fragment identifiers.

Long-Term Fix:

• The vendor must release a patched version that sanitizes user input before DOM insertion (e.g., using textContent instead of innerHTML, or encoding HTML entities).
• Monitor the WordPress plugin repository for updates.

Workaround:

• Disable the Nativery plugin functionality via a custom filter or by removing the vulnerable JavaScript file.

Valters IT