WordPress Extensions For CF7 Plugin Arbitrary File Upload Vulnerability

The Extensions For CF7 (Contact form 7 Database, Conditional Fields and Redirection) plugin for WordPress is vulnerable to Arbitrary File Upload.

Affected versions and conditions:

• All versions up to, and including, 3.4.5.
• The issue is in the extcf7_submit function, via the signature field's validation_filter().
• Missing file extension, MIME type, and size validation, plus no PHP-execution guards in the upload directory.
• A sanitize_file_name() bypass converts shell.php- into shell.php.
• Unauthenticated attackers can upload executable files, leading to remote code execution.