In this talk, I will describe how crypto can sometimes fail to meet its security goals and can leave systems vulnerable to attack. SSH is a widely used secure network protocols which was originally designed as a replacement for insecure remote login procedures. I will present a variety of plaintext-recovery attacks against SSH. I show why a combination of flaws in the basic design of SSH leads implementations such as openSSH to be open to these attacks and why the previous analyses of SSH did not discover such attacks