From: john@csplan9.rit.edu
To: 9fans@cse.psu.edu
Subject: Re: [9fans] a challenge
Date: Fri, 22 Feb 2008 12:59:28 -0500 [thread overview]
Message-ID: <6d112b639dc2e59034939daf3e6d09c3@csplan9.rit.edu> (raw)
In-Reply-To: <13426df10802220953q3af4a1aarf93acaaebfedc9b@mail.gmail.com>
> here is a challenge. I realize it's linux but I think this is the
> right group to ask anyway; I think you'll appreciate the humor in it.
> So far few I have talked to have gotten it.
>
> There is a file, called /bin/bash.
>
> You are allowed to do this as root.
> cp this file to /tmp. Do something to it to make it so that, when you
> are not root, you can run the file in /tmp and get a root shell.
>
> Don't assume the obvious. And please don't post "that's trivial" until
> you have actually done it.
>
> ron
On Debian, all you have to do is this as root:
cp /bin/bash /tmp/sh
chmod u+s /tmp/sh
Then you can run /tmp/sh as any user and get euid root. It seems that
you can ONLY do this if you rename bash to sh.
John
next prev parent reply other threads:[~2008-02-22 17:59 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-02-22 17:53 ron minnich
2008-02-22 17:57 ` Pietro Gagliardi
2008-02-22 18:03 ` Pietro Gagliardi
2008-02-22 17:59 ` john [this message]
2008-02-22 18:23 ` andrey mirtchovski
2008-02-22 18:33 ` ron minnich
2008-02-22 18:57 ` lucio
2008-02-22 20:02 ` Charles Forsyth
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