Pavel Durov cited a security issue disclosed by WhatsApp last week that allowed a hacker to hijack a person’s phone by sending a malicious video to their number.
“Hackers could have full access (!) to everything on the phones of WhatsApp users,” he claimed on Telegram.
“Every year we learn about some issue in WhatsApp that puts everything on their users’ devices at risk... It doesn’t matter if you are the richest person on Earth – if you have WhatsApp installed on your phone, all your data from every app on your device is accessible.”
The Russian tech billionaire, who lives in self-imposed exile from his home country, claimed that the security flaws are “planted backdoors” to allow governments, law enforcement agencies and hackers to bypass the encryption and other security measures.
Mr Durov has previously claimed that “WhatsApp will never be secure” unless there are fundamental changes made to how it works.
Telegram, which is known for taking a privacy-first approach to its app, has more than 700 million active users, with steady growth of roughly 2 million users per day.
This is still just a fraction of the userbase of WhatsApp, which counts roughly 2 billion users worldwide. It is the world’s most popular messageing app ahead of the Chinese-owned app WeChat and Facebook Messenger, which like WhatsApp is owned by Meta.
“I’m not pushing people to switch to Telegram here... Telegram doesn’t need additional promotion,” Mr Durov wrote.
“You can use any messaging app you like, but do stay away from WhatsApp – it has now been a surveillance tool for 13 years.”
The Independent has reached out to WhatsApp for comment.