X2Go Bug report logs - #287
Linux Mint desktops configured too insecurely for multi-user mode

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Package: x2goserver; Maintainer for x2goserver is X2Go Developers <x2go-dev@lists.x2go.org>; Source for x2goserver is src:x2goserver.

Reported by: David Fuhrmann <fuhrmann_mail@web.de>

Date: Wed, 7 Aug 2013 05:48:02 UTC

Severity: critical

Tags: confirmed, moreinfo, wontfix

Found in version 4.0.1.6

Done: Mike Gabriel <mike.gabriel@das-netzwerkteam.de>

Bug is archived. No further changes may be made.

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X-Loop: owner@bugs.x2go.org
Subject: Bug#287: [X2Go-Dev] Bug#287: x2goserver allows to connect to ALL X server sessions by default
Reply-To: Mike Gabriel <mike.gabriel@das-netzwerkteam.de>, 287@bugs.x2go.org
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Date: Wed, 07 Aug 2013 11:43:38 +0200
From: Mike Gabriel <mike.gabriel@das-netzwerkteam.de>
To: David Fuhrmann <fuhrmann_mail@web.de>, 287@bugs.x2go.org
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[Message part 1 (text/plain, inline)]
control: tag -1 moreinfo
control: tag -1 not-a-bug
control: tag -1 wontfix

On Mi 07 Aug 2013 07:36:18 CEST David Fuhrmann wrote:

> I just noticed that x2goserver allows to connect to ALL running X  
> sessions on the target machine, using "connect to local desktop".  
> These might be logged in local users, or NX sessions which were not  
> terminated correctly. This is especially worse in the latter case,  
> as the screen is not locked here, normally.
>
> This is a HUGE security leak, as now all users are able to access  
> data of the other users, and hinder them from working by  
> manipulating current sessions.
>
> Normal remote desktop software should BLOCK such access by default,  
> and only allow it when the user explicitly requested it or  
> configured it so.

I just tested this to be really sure that this is a not-a-bug report...

What you describe only works for the same login!!!! So if my user  
(sunweaver) logs in locally to an X-Session and ,,sunweaver'' then  
connects via X2Go to connect to a local X session then I can access my  
__own__ local X sessions.

However, I cannot access other users' sessions unless they grant  
access via the X2Go Desktop Sharing utility.

Please re-test and re-confirm or post a message that states that the  
mistake was on your part.

Thanks+Greets,
Mike


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