How to protect private keys?

[Joseph Oreste Bruni]

On Apr 12, 2007, at 8:50 PM, Robert J. Hansen wrote:

>> to export private keys, without need to enter passphrase. This is  
>> very
>> dangerous to a multi-user computer.
>
> Clearly, you don't trust the computer you share with other users.  So
> why, exactly, are you running GnuPG on it?
>
> Running GnuPG on a computer you don't trust is folly.  If you don't
> have physical security over the machine, there is no possibility of
> electronic security in your communications.
>
> Beware of all other answers you receive to this question.  Before you
> try to fix the "GnuPG problem", fix the much bigger and more pressing
> problem about how you're trying to run security-critical software on
> a computer you don't physically control.

Indeed. A more pressing question is who has "root" access to the  
system. If any of the users with root access replace the gpg  
executable, then any private key can be compromised.