Update March 8, 2022: EFF has clarified that Channels and Groups are not fully encrypted, end-to-end, updated our post to link to Telegram’s FAQ for Cloud and Secret chats, updated to clarify that auto-delete is available for group and channel admins, and added some additional links. However, the perpetrators of such frauds are now adopting new methods and technologies to defraud the investors. 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. Groups are also not fully encrypted, end-to-end. This includes private groups. Private groups cannot be seen by other Telegram users, but Telegram itself can see the groups and all of the communications that you have in them. All of the same risks and warnings about channels can be applied to groups. Despite Telegram's origins, its approach to users' security has privacy advocates worried.
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