Re: bsdbsdftpd-6.0-ssl-0.6.1-1 attack allows remote users identification

[NetExpress <netexpress () tiscali it>]

Damian Gerow wrote:

> Thus spake NetExpress (netexpress () tiscali it) [16/05/03 16:42]:
>  
>
> > Product bsbsdftpd-6.0-ssl-0.6.1-1 http://bsdftpd-ssl.sc.ru/
> >
> > During a pen-test we have notice how is easy to identify valid users on
> > vulnerable systems, through a simple timing attack.
> >
> > When I try to connect to ftp without ssl using a unreal user with bad 
> > password I get
> > immediatly response of incorrect login, when I use real user with bad
> > password I get 2 second of wait before get message of incorrect login.
> >
> > It seems to be very nice to the recent CAN-2003-0190 about OpenSSH/PAM
> > timing attack allows remote users identification
> >
> > I have tested this on Linux RH 7.3 and RH 8.0
> >    
>
> I just tried this out on a FreeBSD system (4.8-RC x2), and I get the same
> response time.  Are you sure this is directly related to the ftp daemon, or
> is it a PAM issue?
>  
You are right, is the same preoblem has affected OpenSSH/PAM timing 
attack about which Marco Ivald  from MediaService has post the bug and 
the solution.

I have been in touch with Marco Ivaldi, he has found that  is the same 
kind of problem, an the same soltion, but is not really goot to get this 
problem on the default installation . I mailed to the author but  I get 
no response

For the solution follow the same present on 
http://lab.mediaservice.net/advisory/2003-01-openssh.txt

Alessandro Fiorenzi