Re: SSH1 vulnerability ?

[Markus Friedl <Markus.Friedl () INFORMATIK UNI-ERLANGEN DE>]

Tatu Ylonen wrote:

> > > It's real enough for most vendors to respond. I think you want
> > > to make sure your servers have at least 1.2.30/2.4.0 or
> > > openssh 2.3.0p1 at this point.
> >
> > well, 1.2.30 does not contain a fix for this problem.
>
> No, but the current version is ssh-2.4.0, which does not suffer from this
> problem at all.

Well, you have to be very careful.

This is only true if ssh-2.4.0 has fallback to ssh1 disabled
and since the posting says "1.2.30/2.4.0" it implies that ssh1 support
is enabled.

So I'd like to point out again that:

        1) ssh-2.4.0 is vulnerable iff fallback to ssh1 is enabled
           (unless if falls back to openssh-2.3.0p1, but I assume that
           this is very unlikely).

        2) openssh-2.3.0p1 is _not_ vulnerable at all.

Note that it's not unlikely that ssh-2.x installations have ssh1 fallback
_enabled_  (> 50% in the network I did check).

-m