Subverting Telegram’s End-to-End Encryption | IACR
｢ Our attack exploits MTProto2.0’s degree of freedom in choosing the random padding length and padding value. Accordingly, we strongly recommend that Telegram should revise MTProto2.0’s padding methodology. In particular, we show that a minor change in the padding description of MTProto2.0 makes it subversion-resistant in most of the practical scenarios ｣
