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Date: Fri, 12 Apr 2013 21:40:53 -0600
From: Erik Falor <ewfalor AT gmail DOT com>
To: cygwin AT cygwin DOT com
Subject: Re: /dev/tcp support in bash shell
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On Fri, Apr 12, 2013 at 09:12:01PM -0400, Larry Hall (Cygwin) wrote:
> On 4/12/2013 7:49 PM, Andrey Repin wrote:
> >Greetings, Cary Lewis!
> >
> >>Are there any plans to add /dev/tcp/... support in Cygwin?
> >
> >Any use cases for that?
>=20
> Here's one:
>=20
> <http://www.linuxjournal.com/content/more-using-bashs-built-devtcp-file-t=
cpip>
>=20
> Bye, bye Chrome. ;-)

I have really mixed feelings about this feature of Bash.  It can be a
real lifesaver on systems where tools like wget, curl or even netcat
are missing.  On the other hand, it could be a big security risk:

http://www.gnucitizen.org/blog/reverse-shell-with-bash/

http://pentestmonkey.net/cheat-sheet/shells/reverse-shell-cheat-sheet

Despite the ease of allowing a reverse shell or some other exploit to
occur, I think there are far more powerful and exploitable holes in a
system than Bash.  But maybe I'm just not paranoid enough...

--=20
Erik Falor                                       http://unnovative.net
Registered Linux User #445632                  http://linuxcounter.net

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