For whatsapp they do, and they had done so in recent spyware attacks based on 0-days > If we believe that your device has come under threat, we may notify you

For whatsapp they do, and they had done so in recent spyware attacks based on 0-days > If we believe that your device has come under threat, we may notify you about it directly via a WhatsApp chat. The chat will include a system message at the top of the chat that verifies that this is the official account of WhatsApp Support, and there will be a blue checkmark next to WhatsApp Support at the top of the chat. You may also contact us in-app by clicking here. https://faq.whatsapp.com/641700318302674/ https://faq.whatsapp.com/641700318302674/