Attack on krb-priv and krb-safe messages

[Danny Kruitbosch]

Hi,

I've got 2 questions:

1. If a passive attacker who has successfully obtained a user's password,
how would the attacker be able to read the encrypted messages between the
client and server (KRB-PRIV messages). How would he decrypt them? What
steps should he follow? Can such a thing be prevented?

2. How would a active attacker who has succesfully obtained a user's
password insert messages of it's liking in the communication between
client and server (KRB-SAFE messages)? 


Any input on this would be great!


Regards,


Danny