#509 - Document NX/X11 security issue: clipboard sniffing

X2Go Bug report logs - #509
Document NX/X11 security issue: clipboard sniffing

Reported by: Christoph Anton Mitterer <calestyo@scientia.net>

Date: Mon, 1 Jul 2013 02:48:02 UTC

Severity: grave

Tags: security

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From: Mike Gabriel <mike.gabriel@das-netzwerkteam.de>
To: x2go-user@lists.berlios.de
Cc: 258@bugs.x2go.org
Subject: Re: [X2Go-User] Limiting clipboard sharing
References: <52E69B93.8010904@sourcecap.ch>
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Hi Kris, On Mo 27 Jan 2014 18:46:59 CET, Kris Ilowiecki wrote: > Hello, > > I am quite new to X2Go, and really impressed by it. I'd like to > switch from opennx to X2Go, but I can't find a way to limit > clipboard sharing. > > Opennx, as well as other NX forks, has the options to enable clipboard > sharing both ways, one-way, or disable it completely. So far I have > failed to find a setting to limit this in X2Go. > > I'd need clipboard sharing to work only in the client->server > direction, or at least to disable it completely. > > I have searched for it for quite a while, but the best I have > managed to find is a bug report > http://bugs.x2go.org/cgi-bin/bugreport.cgi?bug=258 > and a mailing list question without a single reply. > > Is there some way to configure it? > If not, is it going to be hard to write a patch that would turn > this off at compilation time? > I've also been thinking of using some external programs to achieve > the effect, e.g. putting X2Go inside Xephyr, or the other way round... > > Any hints most welcome > > Many thanks, > Kris There should be two approaches... 1) disable clipboard server-side for all users 2) disable clipboard in X2Go Client / PyHoca-GUI on the client-side The first is easy. Please look at /usr/bin/x2gostartagent of x2goserver package and make clipboard configurable via /etc/x2go/x2goserver.conf. Send a patch to our BTS [1]. The second approach is for us devs, I guess... The workaround provided by Mike#2 is a fine approach, but not a real solution to this problem. Mike#1 [1] http://wiki.x2go.org/doku.php/wiki:bugs -- DAS-NETZWERKTEAM mike gabriel, herweg 7, 24357 fleckeby fon: +49 (1520) 1976 148 GnuPG Key ID 0x25771B31 mail: mike.gabriel@das-netzwerkteam.de, http://das-netzwerkteam.de freeBusy: https://mail.das-netzwerkteam.de/freebusy/m.gabriel%40das-netzwerkteam.de.xfb

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X2Go Bug report logs - #509 Document NX/X11 security issue: clipboard sniffing

X2Go Bug report logs - #509
Document NX/X11 security issue: clipboard sniffing