Individual messages can be fully encrypted. But the user has to turn on that function. It's not automatic, as it is on Signal and WhatsApp. In the past, it was noticed that through bulk SMSes, investors were induced to invest in or purchase the stocks of certain listed companies. In the United States, Telegram's lower public profile has helped it mostly avoid high level scrutiny from Congress, but it has not gone unnoticed. Some privacy experts say Telegram is not secure enough Perpetrators of such fraud use various marketing techniques to attract subscribers on their social media channels.
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