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How can I secure file uploads to prevent malware injection?

Asked on Sep 30, 2025

Answer

To secure file uploads and prevent malware injection, you should implement strict validation, sanitization, and scanning procedures. Here is a structured approach to achieve this:

<!-- BEGIN COPY / PASTE -->
    // Example of file validation in PHP
    $allowedMimeTypes = ['image/jpeg', 'image/png', 'application/pdf'];
    $fileMimeType = mime_content_type($_FILES['uploadedFile']['tmp_name']);

    if (in_array($fileMimeType, $allowedMimeTypes)) {
        // Proceed with file processing
    } else {
        // Reject the file
    }
    <!-- END COPY / PASTE -->

Additional Comment:

Always validate the file type and size on the server side, not just client side.
Use a virus scanning service or library to scan files for malware before processing.
Store uploaded files outside of the web root to prevent direct access.

✅ Answered with Security best practices.

Ask any question about Website Security here... and get an instant response.

How can I secure file uploads to prevent malware injection?

Asked on Sep 30, 2025

Answer

Additional Comment:

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