Unix-pc Security

[Hans Jespersen]

Since the topic of security is very hot right now, I thought I'd share 
a little trick I learned resently. 3.51 (and others I believe)  come
default with VERY liberal permissions on /. I think it might even be
777. Anyhow, the trick is to create a fake passwd file in a directory
off / (ie. /newetc/passwd). Modify this passwd file to suit. 
Then IN ONE LINE type :

mv /etc /oldetc;mv /newetc /etc

This must be done in one line or the box will crash. If a system process 
comes along and sees that there is no passwd file that's it.

Anyway, the moral of the posting is CHECK YOUR PERMISSIONS particularity
with regard to the / directory.

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Hans Jespersen           | uunet!watmath!trillium!hjespersen
University of Waterloo   | "Defn. of Natural Logarithm - A lumbarjacks
Waterloo, Ontario        | idea of birth control."
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