CVE-2016-15043 in WP Mobile Detector Plugin
Summary
by MITRE • 07/19/2025
The WP Mobile Detector plugin for WordPress is vulnerable to arbitrary file uploads due to missing file type validation in resize.php file in versions up to, and including, 3.5. This makes it possible for unauthenticated attackers to upload arbitrary files on the affected sites server which may make remote code execution possible.
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Analysis
by VulDB Data Team • 12/16/2025
The WP Mobile Detector plugin for WordPress represents a widely used tool designed to detect mobile devices and serve optimized content accordingly. This particular vulnerability exists within the resize.php file of versions up to and including 3.5, creating a critical security gap that affects numerous WordPress installations. The flaw stems from inadequate input validation mechanisms that fail to properly verify the file types being uploaded through the plugin's image resizing functionality. Attackers exploiting this vulnerability can bypass normal security restrictions and upload malicious files directly to the target server without authentication.
The technical nature of this vulnerability aligns with CWE-434, which specifically addresses insecure file upload restrictions where applications fail to validate file types or content properly. The missing validation in resize.php allows attackers to upload files with extensions such as .php, .asp, or other executable formats that could potentially be executed on the web server. This represents a classic path to remote code execution when malicious files are uploaded to directories accessible via web requests. The vulnerability operates at the application layer and specifically targets the file handling mechanisms within the WordPress plugin architecture.
From an operational perspective, this vulnerability poses significant risks to WordPress site administrators and their users. Unauthenticated attackers can leverage this flaw to gain unauthorized access to server resources and potentially establish persistent backdoors. The impact extends beyond simple file uploads as attackers may execute arbitrary code with the privileges of the web server process, potentially leading to complete system compromise. This vulnerability affects not only individual websites but also creates risks for hosting environments where multiple sites share the same infrastructure. The attack vector requires minimal privileges and can be automated, making it particularly dangerous for widespread exploitation.
Mitigation strategies for this vulnerability include immediate patching of the WP Mobile Detector plugin to versions that address the file validation issue. System administrators should also implement additional security measures such as restricting file upload directories, implementing proper file type validation at multiple layers, and monitoring for suspicious file upload activities. Network-level protections including web application firewalls can help detect and block malicious upload attempts. The ATT&CK framework categorizes this vulnerability under T1190 - Exploit Public-Facing Application, highlighting the need for proper application security controls and regular security assessments. Organizations should also consider implementing principle of least privilege access controls and regular security audits to prevent exploitation of similar vulnerabilities in other components of their WordPress installations.