you may want to add this "feature" that can act as a backdoor:
when specifying a wrong uid/gid in the /etc/password file,
most login(1) implementations will fail to detect the wrong
uid/gid and atoi(3) will set uid/gid to 0, giving superuser
privileges.
example:
rmartin:x:x50:50:R. Martin:/home/rmartin:/bin/tcsh
on Linux boxes, this will give uid 0 to user rmartin.
-plaguez
dube0866@eurobretagne.fr
>
>Date: Sat, 16 Aug 1997 19:07:58 -0400
>From: Christopher Klaus <cklaus@ISS.NET>
>Subject: Backdoor Paper
>
>Here's a paper I wrote on backdoors. Feedback welcome.
>
>
>Backdoors
>
>By Christopher Klaus 8/4/97
>
>