CVE-2025-54023

Executive Summary

CVE-2025-54023 is a DOM-Based Cross-Site Scripting (XSS) vulnerability discovered in the WP Delicious WordPress plugin, specifically within the delicious-recipes component. This vulnerability affects all versions up to and including 1.8.4. The flaw arises from improper neutralization of user-supplied input during web page generation, allowing an attacker to inject malicious scripts that execute in the victim's browser within the context of the vulnerable WordPress site.

As a WordPress plugin vulnerability, this issue is confined to the WordPress ecosystem and does not implicate the underlying web server (Apache/Nginx). The attack vector is network-based, requires low complexity, and necessitates user interaction (e.g., clicking a crafted link). Successful exploitation could lead to session hijacking, credential theft, defacement, or redirection to malicious sites.

Key Risk Factors:

• No public exploit or PoC is currently available.
• No official patch has been released by the vendor.
• EPSS score is 0.0%, indicating very low exploitation activity in the wild at this time.
• The vulnerability is DOM-based, meaning the payload is executed entirely client-side, often bypassing server-side filters.

Supply Chain & Package Security

This vulnerability affects a WordPress plugin distributed via the official WordPress plugin repository. Users who installed the plugin directly from the WordPress dashboard or via manual upload are affected. There is no known compromise of the plugin's distribution channel; the vulnerability is a code-level flaw in the plugin itself.

CVSS Breakdown & Threat Level

CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:L

Base Score: 6.5 (Medium)

Threat Level: Medium. While the CVSS score is moderate, the lack of a patch and the potential for DOM-based attacks that can bypass traditional WAFs elevate the risk for unpatched installations.

Deep Dive & Mechanics

The vulnerability resides in the delicious-recipes plugin's JavaScript code, which processes user input from the DOM (e.g., URL fragments, document.referrer, window.name, or form fields) and injects it into the page without proper sanitization. DOM-based XSS differs from reflected/stored XSS because the payload never reaches the server; it is executed entirely within the client's browser.

Attack Flow:

1. An attacker crafts a malicious URL containing a JavaScript payload in a fragment identifier (e.g., #<script>alert('XSS')</script>) or a query parameter.
2. The victim clicks the link, which loads the vulnerable WordPress page.
3. The plugin's JavaScript reads the malicious input from location.hash or document.URL.
4. The input is directly written to the DOM using methods like innerHTML, document.write, or eval() without sanitization.
5. The injected script executes in the victim's browser, allowing the attacker to steal cookies, redirect the user, or perform actions on behalf of the victim.

Root Cause: The plugin fails to use safe DOM manipulation methods (e.g., textContent instead of innerHTML) and does not encode or validate input before rendering.

Vulnerable vs. Patched Code

Since no official patch is available, the following is a hypothetical comparison based on common remediation patterns.

Vulnerable Code (JavaScript):

// Vulnerable: Directly using innerHTML with unsanitized input
var userInput = window.location.hash.substring(1);
document.getElementById('recipe-title').innerHTML = userInput;

Patched Code (Hypothetical):

// Patched: Using textContent to prevent HTML injection
var userInput = window.location.hash.substring(1);
document.getElementById('recipe-title').textContent = userInput;

Alternative Patched Code (with sanitization):

// Patched: Using DOMPurify to sanitize input
var userInput = window.location.hash.substring(1);
var cleanInput = DOMPurify.sanitize(userInput);
document.getElementById('recipe-title').innerHTML = cleanInput;

Exploitation & Lab Setup

Red Team (Proof of Concept)

Since no public exploit exists, the following is a conceptual PoC for educational purposes.

Step 1: Identify vulnerable endpoint

• Navigate to a page using the delicious-recipes plugin (e.g., a recipe page).
• Look for JavaScript that reads location.hash or document.URL and writes to the DOM.

Step 2: Craft malicious URL

http://target-site.com/recipe/chocolate-cake/#<img src=x onerror=alert(document.cookie)>

Step 3: Deliver to victim

• Send the link via email, social media, or embed in an iframe.

Step 4: Observe execution

• The victim's browser executes the injected script, displaying an alert with their cookies.

Blue Team (Detection & Hardening)

Detection:

• Monitor web server logs for requests containing suspicious patterns in the URL fragment (e.g., <script, onerror=, javascript:).
• Use browser-based CSP (Content Security Policy) headers to block inline scripts.

Hardening:

• Immediate: Disable or remove the delicious-recipes plugin until a patch is available.
• Workaround: Implement a Web Application Firewall (WAF) rule to block requests with malicious fragments (though DOM-based XSS is harder to filter).
• Long-term: Apply the principle of least privilege and use a plugin vulnerability scanner.

Indicators of Compromise (IOCs)

Network IOCs:

• HTTP requests containing # followed by JavaScript event handlers (e.g., #<script, #<img, #<svg).
• Referer headers from known malicious domains.

Host IOCs:

• Unexpected JavaScript files in the wp-content/plugins/delicious-recipes/ directory.
• Modified plugin files (check file integrity via checksums).
• Browser console errors related to DOM manipulation.

Log IOCs:

• Web server logs showing %23 (URL-encoded #) followed by script tags.
• Unusual window.location.hash values in JavaScript error logs.

Detection Engineering

YARA Rule

rule CVE_2025_54023_DOM_XSS {
    meta:
        description = "Detects potential DOM-based XSS in WP Delicious plugin"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2025-54023"
    strings:
        $vuln_func1 = "innerHTML" nocase
        $vuln_func2 = "document.write" nocase
        $vuln_func3 = "eval(" nocase
        $vuln_source1 = "location.hash" nocase
        $vuln_source2 = "document.URL" nocase
        $vuln_source3 = "document.documentURI" nocase
    condition:
        any of ($vuln_func*) and any of ($vuln_source*)
}

Sigma Rule

title: CVE-2025-54023 DOM-Based XSS in WP Delicious Plugin
id: 8a9b7c6d-5e4f-3a2b-1c0d-9e8f7a6b5c4d
status: experimental
description: Detects potential exploitation attempts of DOM-based XSS in WP Delicious plugin
author: Valters IT
date: 2025/04/10
logsource:
    category: webserver
    product: apache
    service: access_log
detection:
    selection:
        cs-uri-query|contains:
            - '#<script'
            - '#<img'
            - '#<svg'
            - '#<iframe'
            - 'onerror='
            - 'onload='
            - 'onmouseover='
    condition: selection
falsepositives:
    - Legitimate use of hash fragments in URLs
level: medium

Suricata Rule

alert http any any -> any any (msg:"CVE-2025-54023 WP Delicious DOM XSS Attempt"; flow:to_server,established; content:"#<script"; http_uri; nocase; sid:1000001; rev:1;)
alert http any any -> any any (msg:"CVE-2025-54023 WP Delicious DOM XSS Attempt 2"; flow:to_server,established; pcre:"/#(?:<script|<img|<svg|<iframe|onerror=|onload=|onmouseover=)/iU"; sid:1000002; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Disable the plugin: Deactivate and delete the delicious-recipes plugin from the WordPress admin panel.
2. Monitor for updates: Check the WordPress plugin repository and the vendor's website for a patched version.
3. Implement CSP: Add a Content Security Policy header to block inline scripts:

   Content-Security-Policy: default-src 'self'; script-src 'self'; object-src 'none';
   

Long-term Fixes:

• Apply vendor patch: Once released, update to the latest version immediately.
• Code review: If you are a developer, audit the plugin's JavaScript for unsafe DOM manipulation and replace with safe alternatives (e.g., textContent, setAttribute).
• Use a security plugin: Employ a WordPress security plugin that includes XSS protection and file integrity monitoring.

Workarounds:

• WAF rules: Create custom WAF rules to block requests containing #<script or similar patterns.
• Input validation: If you must keep the plugin, modify the JavaScript to sanitize input using a library like DOMPurify.

Valters IT
Securing Digital Frontiers