Telegram 0-day vulnerability that can be used to disclose user's phone numbers

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25 pointsseapunk5 comments

Sounds like it doesn't directly give you a user <=> phone number mapping, but allows to confirm whether the user with phone number X is in a public channel, which is bad enough.

https://news.ycombinator.com/item?id=20776327

lol "0-day vulnerability". I've known this since forever, everybody does. If you have someone on your contact list you see them with the name you've stored them as on your contact list in groups too.

Telegram is not e2e encrypted by default and group chats can simply not be encrypted. Whoever uses Telegram expecting security is a dunce.

Honestly, your comment is not very constructive. Did you create this account only to critize and lessen this security issue?

It's as constructive as yours.

I'm serious. Your url about the previous HN post was relevant but the rest of your message sounds really defiant. Just an honest feedback about what I feel.

Reply on news.ycombinator.com