SSH hacked?

[CLIFFORD ILKAY]

Kent Borg wrote:
> Knute Johnson wrote:
>> Why use passwords at all with SSH? The public key authentication is
>> several orders of magnitude harder to crack than username/password.
>> And it is really easy to use.
> 
> I keep records of all the passwords I use. I keep that list encrypted.
> (And who says the encrypted list is even on my computer?)
> 
> Private ssh keys, on the other hand, need to be in the clear to be
> useful. I get nervous having such valuable data sitting in the clear. A
> little misconfiguration and Apache might serve up my keys, or they might
> be readable by other users of the system, or some buggy PHP code decides
> to let the world have them. So many security holes I see reported allow
> the bad guys to read files they are not supposed to read. Having private
> ssh keys just sitting there scares me. And having many of them (for
> different systems) scares me. And having multiple copies (on different
> systems) scares me. And the idea of someone cracking into one home
> directory of mine meaning he now has access to all my machines scares
> me. Lots of things to be nervous about.

Why would your private key need to be on a server? You keep your private
key locally and protect it with a strong passphrase and only put your
public key on servers to which you want to connect. For someone to
compromise such a system, they would have to first steal your private
key, then crack the (hopefully) strong passphrase that you should have
used on the private key, and finally figure out which servers will let
them in with that private key. The last part might not be very difficult
but the first two, especially the second, should be very difficult and
certainly no less secure than your "strong passwords" scheme. If you're
still concerned about this scheme, you can still use the same "sooper
sekrit" method you currently use for storing your list of passwords. SSH
defaults to looking for your private key in ~/.ssh but you can specify
an alternate path, such as a USB key.

There is no good reason to use password authentication with SSH.
Key-based authentication is more secure.
-- 
Regards,

Clifford Ilkay
Dinamis
1419-3266 Yonge St.
Toronto, ON
Canada  M4N 3P6

<http://dinamis.com>
+1 416-410-3326
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