CVE-2025-27282: Theme File Duplicator Upload Vulnerability

CVE-2025-27282 Overview

CVE-2025-27282 is an Unrestricted Upload of File with Dangerous Type vulnerability (CWE-434) affecting the Theme File Duplicator WordPress plugin developed by rockgod100. This vulnerability allows authenticated attackers to upload malicious files to vulnerable WordPress installations, potentially leading to complete site compromise through remote code execution.

The vulnerability exists because the plugin fails to properly validate file types during the upload process, enabling attackers to bypass security controls and upload executable files such as PHP web shells. Once uploaded, these malicious files can be accessed directly through the web server, granting attackers the ability to execute arbitrary commands on the underlying system.

Critical Impact

Authenticated attackers can upload and execute malicious files, leading to complete WordPress site takeover, data theft, and potential lateral movement within the hosting infrastructure.

Affected Products

• Theme File Duplicator plugin versions 1.3 and earlier
• WordPress installations running vulnerable versions of Theme File Duplicator

Discovery Timeline

• 2025-04-17 - CVE-2025-27282 published to NVD
• 2025-04-17 - Last updated in NVD database

Technical Details for CVE-2025-27282

Vulnerability Analysis

This vulnerability falls under CWE-434 (Unrestricted Upload of File with Dangerous Type), a well-documented weakness category affecting web applications that handle file uploads. The Theme File Duplicator plugin, designed to duplicate theme files within WordPress, contains insufficient validation controls that fail to restrict dangerous file types during upload operations.

The plugin's upload functionality does not properly verify that uploaded files match expected safe file types. When an authenticated user (even with minimal privileges) submits a file through the plugin's interface, the application accepts the file without adequate checks on its extension, MIME type, or content. This allows PHP files, web shells, and other executable content to be uploaded to the WordPress installation.

Once a malicious file is successfully uploaded to an accessible directory, attackers can invoke it directly via HTTP request, causing the web server to execute the malicious code. This grants attackers the same privileges as the web server process, typically allowing full control over the WordPress installation and potentially the underlying hosting environment.

Root Cause

The root cause of CVE-2025-27282 is the absence of proper file type validation within the Theme File Duplicator plugin's upload handling logic. The plugin fails to implement defense-in-depth measures such as:

• File extension whitelisting to allow only safe file types
• MIME type verification to validate actual file content
• Content inspection to detect executable code signatures
• Secure file storage outside the web root with randomized filenames

Without these controls, the upload functionality becomes a direct vector for injecting malicious code into the WordPress environment.

Attack Vector

The attack vector for this vulnerability is network-based and requires low-privilege authentication. An attacker with any authenticated access to the WordPress installation can exploit this vulnerability through the following attack flow:

1. The attacker authenticates to the WordPress site with minimal user privileges
2. The attacker accesses the Theme File Duplicator plugin's upload functionality
3. A malicious file (e.g., PHP web shell) is crafted and submitted through the upload mechanism
4. The plugin accepts the file without proper validation and stores it in an accessible location
5. The attacker navigates to the uploaded file's URL, triggering execution of the malicious code
6. The attacker gains command execution capabilities on the target server

The vulnerability has a changed scope impact, meaning successful exploitation can affect resources beyond the vulnerable component itself, potentially compromising the entire web server and other hosted applications.

Detection Methods for CVE-2025-27282

Indicators of Compromise

• Unexpected PHP files appearing in WordPress theme directories or upload folders
• Web shell signatures such as eval(), base64_decode(), system(), or passthru() functions in uploaded files
• Unusual outbound network connections from the web server process
• New or modified files in /wp-content/themes/ or /wp-content/uploads/ directories with recent timestamps

Detection Strategies

• Monitor WordPress plugin directories for newly created or modified PHP files outside of normal update cycles
• Implement Web Application Firewall (WAF) rules to detect file upload attempts containing PHP code or shell commands
• Deploy file integrity monitoring on WordPress installations to alert on unauthorized file changes
• Review web server access logs for requests to unusual file paths within theme or upload directories

Monitoring Recommendations

• Enable verbose logging for the Theme File Duplicator plugin and all file upload operations
• Configure real-time alerting for any new executable file creation in WordPress directories
• Implement endpoint detection and response (EDR) solutions like SentinelOne to monitor for post-exploitation activity such as reverse shells or privilege escalation attempts
• Regularly audit WordPress user accounts to identify unauthorized or suspicious accounts that could be used for exploitation

How to Mitigate CVE-2025-27282

Immediate Actions Required

• Deactivate and remove the Theme File Duplicator plugin immediately if running version 1.3 or earlier
• Audit WordPress theme and upload directories for suspicious PHP files or web shells
• Review WordPress user accounts and revoke access for any unauthorized or unnecessary accounts
• Check web server logs for evidence of exploitation attempts or successful compromise

Patch Information

As of the publication date, no patched version has been confirmed for Theme File Duplicator. Website administrators should consult the Patchstack vulnerability database for the latest patch status and updates from the plugin developer.

If a patch becomes available, administrators should:

1. Back up the WordPress installation before applying updates
2. Update to the patched version through the WordPress admin interface or via WP-CLI
3. Verify the update was successful and test site functionality
4. Continue monitoring for any signs of prior compromise

Workarounds

• Remove or deactivate the Theme File Duplicator plugin entirely until a security patch is released
• Implement server-level restrictions to block PHP execution in upload directories using .htaccess rules or web server configuration
• Deploy a Web Application Firewall (WAF) with rules to block malicious file upload attempts
• Restrict WordPress admin panel access to trusted IP addresses only
• Ensure WordPress user accounts follow the principle of least privilege, limiting the number of users with upload capabilities

# Apache .htaccess rule to prevent PHP execution in uploads directory
# Place this file in /wp-content/uploads/.htaccess
<FilesMatch "\.php$">
    Deny from all
</FilesMatch>

# Alternative: Disable PHP execution entirely in directory
php_flag engine off