CVE-2025-67937

Executive Summary

CVE-2025-67937 is a critical security vulnerability affecting the Hendon WordPress theme developed by Mikado-Themes. The vulnerability is classified as a PHP Local File Inclusion (LFI) due to improper control of a filename used in a PHP include/require statement. An unauthenticated attacker can exploit this flaw to read arbitrary files from the server, potentially exposing sensitive configuration files, database credentials, or source code. The CVSS score of 8.1 reflects the high confidentiality impact and ease of exploitation over the network without authentication. As of this report, no official patch has been released, and no public proof-of-concept (PoC) code is available.

Supply Chain & Package Security

This vulnerability resides in a WordPress theme, which is part of the broader WordPress ecosystem. WordPress themes are distributed via the official WordPress repository, commercial marketplaces, or directly from developers. The supply chain risk is significant because:

• Unpatched themes can be deployed on thousands of sites, creating a large attack surface.
• Automatic updates may not be enforced for premium themes, leaving sites vulnerable.
• Third-party dependencies within the theme (e.g., bundled plugins or libraries) could also be affected.

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): None (N) – No user action required.
• Scope (S): Unchanged (U) – The vulnerability does not affect other components.
• Confidentiality (C): High (H) – Full file read access.
• Integrity (I): None (N) – No file modification.
• Availability (A): None (N) – No denial of service.

Threat Level: High. The combination of network exploitability, no authentication, and high confidentiality impact makes this a serious threat for any site using the Hendon theme.

Deep Dive & Mechanics

The vulnerability stems from a PHP Local File Inclusion (LFI) in the Hendon theme. The theme likely uses a function like include() or require() with a user-supplied parameter (e.g., via $_GET or $_POST) without proper sanitization. An attacker can manipulate this parameter to include arbitrary files from the server.

Example vulnerable code pattern:

$file = $_GET['template'];
include($file . '.php');

By passing a path traversal sequence (e.g., ../../../../etc/passwd), the attacker can read sensitive files. The include() function in PHP will execute the file if it contains PHP code, but for non-PHP files, it will output the raw content.

Attack vector: The vulnerability is triggered via a crafted HTTP request to a WordPress page that uses the Hendon theme. The exact parameter is not publicly disclosed, but common vectors include ?template=, ?file=, or ?page=.

Vulnerable vs. Patched Code

Since no patch is available, we can only infer the vulnerable pattern. A secure implementation would validate the filename against a whitelist of allowed files or use a mapping array.

Vulnerable code (hypothetical):

$template = $_GET['template'];
include( get_template_directory() . '/templates/' . $template . '.php' );

Patched code (hypothetical):

$allowed_templates = array('home', 'about', 'contact');
$template = $_GET['template'];
if (in_array($template, $allowed_templates)) {
    include( get_template_directory() . '/templates/' . $template . '.php' );
} else {
    // Handle error
}

Exploitation & Lab Setup

Red Team

Prerequisites:

• A WordPress site running the Hendon theme version < 1.7.
• Knowledge of the vulnerable parameter (e.g., template).

Exploitation steps:

1. Identify the vulnerable endpoint by fuzzing common parameters.
2. Send a request to include a sensitive file:

   GET /?template=../../../../etc/passwd HTTP/1.1
   Host: target.com
   

3. If successful, the response will contain the contents of /etc/passwd.

Example curl command:

curl -v "http://target.com/?template=../../../../etc/passwd"

Note: No public exploit code is available, so this is a theoretical approach.

Blue Team

Detection and response:

• Monitor web server logs for path traversal patterns (e.g., ../, ..\\, %2e%2e%2f).
• Deploy a Web Application Firewall (WAF) with rules to block directory traversal attempts.
• Use file integrity monitoring to detect unauthorized file access.

Honeypot suggestion:

• Create a fake sensitive file (e.g., /var/www/html/wp-config.php.bak) and monitor access attempts.

Indicators of Compromise (IOCs)

• Network IOCs:

  • HTTP requests containing ../ or ..\\ in query parameters.
  • Requests to /?template= or similar parameters with path traversal sequences.
  • Unusual file paths in the request URI (e.g., /etc/passwd, /proc/self/environ).

• File IOCs:

  • Unexpected entries in web server access logs showing file inclusion attempts.
  • Presence of temporary files created by the attacker (e.g., /tmp/exploit.php).

• System IOCs:

  • Unauthorized access to /etc/passwd, /etc/shadow, or database configuration files.
  • Suspicious PHP error logs indicating failed include attempts.

Detection Engineering

YARA Rule

rule CVE_2025_67937_LFI_Attempt {
    meta:
        description = "Detects path traversal attempts targeting CVE-2025-67937"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2025-67937"
    strings:
        $path_traversal = /(\.\.\/|\.\.\\){2,}/ nocase
        $sensitive_file = /(etc\/passwd|etc\/shadow|proc\/self\/environ|wp-config\.php)/ nocase
    condition:
        any of them
}

Sigma Rule

title: CVE-2025-67937 LFI Attempt
id: 8a9b7c6d-5e4f-3a2b-1c0d-9e8f7a6b5c4d
status: experimental
description: Detects path traversal attempts in HTTP requests targeting the Hendon theme
author: Valters IT
date: 2025-04-10
references:
    - https://nvd.nist.gov/vuln/detail/CVE-2025-67937
logsource:
    category: webserver
    product: apache
    service: access_log
detection:
    selection:
        cs-uri-query|contains:
            - '../'
            - '..\\'
            - '%2e%2e%2f'
            - '%2e%2e%5c'
    condition: selection
falsepositives:
    - Legitimate use of relative paths in some applications
level: high

Suricata Rule

alert http any any -> any any (msg:"CVE-2025-67937 LFI Attempt"; flow:to_server,established; content:"../"; http_uri; nocase; content:"/etc/passwd"; http_uri; nocase; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate actions:

1. Disable the Hendon theme and switch to a secure alternative until a patch is released.
2. Apply a virtual patch using a WAF to block path traversal patterns.
3. Restrict file permissions on sensitive files (e.g., wp-config.php should be readable only by the web server user).

Long-term fixes:

• Update the theme to version 1.7 or later once a patch is available.
• Implement input validation for all user-supplied parameters used in file operations.
• Use a whitelist approach for allowed files instead of blacklisting.

Workaround:

• Add the following rule to .htaccess to block path traversal:

  RewriteEngine On
  RewriteCond %{QUERY_STRING} (\.\./|\.\.\\) [NC]
  RewriteRule .* - [F,L]
  

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