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Date: Wed, 03 Dec 2008 03:01:25 -0800
From: Brian Dessent <brian AT dessent DOT net>
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Subject: Re: Finally managed to create a jailed SFTP server, but how secure?
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Julio Emanuel wrote:

> 4) Only commands compiled for Cygwin, AND accessing the file system
> exclusively through the Cygwin POSIX interfaces can (and will) obey
> the chroot settings;

This is not valid reasoning, as Eric Blake already pointed out you can
still access files outside of a chroot even if you're still going
through the Cygwin DLL by using Win32 style pathnames since Cygwin
passes those through untouched.  Whether or not you can trick the sftp
code into letting such a filename through remains to be seen, but the
point here is that just because the access occurs via the Cygwin API
doesn't mean the chroot is absolute.

Brian

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