Telegram Founder Pavel Durov attacked WhatsApp after the recent incident, in which, WhatsApp fixed a high severity bug that allows hackers to inject spyware remotely by making a single WhatsApp call and steal entire phone data. Telegram was created by people who had to leave Russia because of restrictions on freedom and privacy. WhatsApp is not an open source platform and it never allows security researchers to check whether the App contain any malicious code or stealing any data from users. He pointed similar incidents (1, 2, 3) and said Every time WhatsApp has to fix a critical vulnerability in their app, a new one seems to appear in its place”]
Source: https://gbhackers.com/whatsapp-will-never-be-secure/