11. SSHv1

• the session key is generated by the client
• then sent it ciphered with the server's public key he just received
  • attacker just have to use any public / private key pair
  • and wait the client accept to use that public key.
• password client authentication:
  • sent in "clear text" in the ciphered tunnel
• RSA client authentication:
  • server sends to client a ciphered challenge with an authorized public key
  • client proves he knows the private key by unciphered the challenge
• sshmitm imposes authentication by password in sshv1.