“Apart from the legal bit, that’s exactly how malware works. It compromises your device in order to gain access to information,” said Signal’s vice-president for global affairs, Udbhav Tiwari.

https://www.techradar.com/vpn/vpn-privacy-security/chat-control-is-like-a-malware-on-your-device-signal-slams-the-eu-proposal-to-scan-your-private-chats