OpenSSH Security Advisory (adv.iss)

[Carson Gaspar]

Use the Source, Luke:

        { "challengeresponseauthentication", 
sChallengeResponseAuthentication },
        { "skeyauthentication", sChallengeResponseAuthentication }, /* 
alias */

One must make sure that neither option is enabled.

        { "PAMAuthenticationViaKbdInt", sPAMAuthenticationViaKbdInt },

Is also suspect, based on the patch, although the advisory isn't sure if 
it's exploitable or not.

--On Wednesday, June 26, 2002 4:42 PM +0200 Markus Friedl 
<markus at openbsd.org> wrote:

> 2. Impact:
>
>         This bug can be exploited remotely if
>         ChallengeResponseAuthentication is enabled in sshd_config.
>
> 	Affected are at least systems supporting
> 	s/key over SSH protocol version 2 (OpenBSD, FreeBSD
> 	and NetBSD as well as other systems supporting
> 	s/key with SSH).  Exploitablitly of systems
> 	using PAM in combination has not been verified.
>
> 3. Short-Term Solution:
> 	
>         Disable ChallengeResponseAuthentication in sshd_config.