Bug#366541: openssh-server: [security] use /bin/nologin instead of /bin/false

[Justin Pryzby <justinpryzby@users.sourceforge.net>]

On Wed, May 10, 2006 at 07:46:20AM +0300, Jari Aalto wrote:
> | severity 366541 wishlist
> | thanks
> | 
> | On Tue, May 09, 2006 at 06:30:00PM +0300, Jari Aalto wrote:
> | > Package: openssh-server
> | > Version: 1:4.2p1-8
> | > Severity: normal
> | > Tags: security
> | > 
> | > The /etc/passwd contains entry:
> | > 
> | >   sshd:x:101:65534::/var/run/sshd:/bin/false
> | > 
> | > SUGGESTION
> | > 
> | > The new login package includes /bin/nologin wich would be more secure, 
> | > because it leaves trace to syslog after login attemps.
> | I think it has the same functional effect:
> |   May  9 12:46:31 andromeda nologin: Attempted login by pryzbyj on /dev/pts/2
> |   May  9 12:47:34 andromeda login[6063]: FAILED LOGIN (1) on `tty1' FOR `sshd', Authentication failure
> |   May  9 12:49:31 andromeda login[25987]: FAILED LOGIN (1) on `tty1' FOR `sshd', Authentication failure
> 
> Not at all. The nologin records the account that ws used to "crack in".
I was unclear.  The first of those lines was when I ran
/usr/sbin/nologin (note that the path is different from what you
suggest) from the shell of an authenticated account.

The other 2 lines are the same, since the shell is never even run; I
guess that this is a request for logging, in the accidental case that
the shell *is* run?

Justin