Telegram founder Pavel Durov has stated that the Facebook-owned WhatsApp would never be safe. He says that hackers could access anything- photos, emails, texts etc- on any phone that had WhatsApp installed on it. He also discusses the security issue about WhatsApp recently faced- that of a high severity bug that could allow hackers to inject spyware remotely into a phone simply by making a WhatsApp call. WhatsApp is not an open source platform and hence it never allows security researchers to easily check if there are backdoors in its code.”]
Source: https://hackercombat.com/whatsapp-will-never-be-safe-says-telegram-founder/