Files Cannot Be Scanned in End-to-End Encrypted Applications

Question

Why are files not scanned in end-to-end encrypted applications such as WhatsApp Web and Telegram Web?

Answer

This is a known limitation. The client can intercept files uploaded through the web browser to WhatsApp Web and Telegram Web, but these files are encrypted. As a result, only the encrypted file can be scanned, and the original file content cannot be analyzed.

Files can be scanned or intercepted if Deep Packet Inspection (DPI) is disabled. Another workaround is to block the domains web.whatsapp.com and web.telegram.org.

As an alternative, use the desktop versions of these applications, which are not monitored via DPI. In this case, files can be blocked as expected.