[pmelendez]

If you read the comments on that blog, telegram actually negate that:

> the server can perform a MITM attack. > you cannot detect MITM between you and your peers.

>> NOT true. You can compare key visualization in the clients.

[nwh]

https://news.ycombinator.com/item?id=6932053

The key is not shown in hex, so a MITM is quite simple.