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

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Message #40 received at 287@bugs.x2go.org (full text, mbox, reply):

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From david.fuhrmann@gmail.com  Wed Aug  7 20:10:48 2013
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Sender: David Fuhrmann <david.fuhrmann@gmail.com>
Subject: Re: [X2Go-Dev] Bug#287: x2goserver allows to connect to ALL X server sessions by default
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From: David Fuhrmann <fuhrmann_mail@web.de>
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Date: Wed, 7 Aug 2013 20:10:44 +0200
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References: <F7C30D2B-5461-457E-8088-7A0933A86EEF@web.de> <20130807114338.13215dfoanwep8sq@mail.das-netzwerkteam.de> <CANN0FUgL27BfEyQ_=4nLiY56rHjo5fGsf1OyDK47vLb2Gdi+jg@mail.gmail.com> <20130807160258.61246yer4vhkibo2@mail.das-netzwerkteam.de> <7590CCCD-172A-4E9A-BF38-49ADA374C4C1@web.de>
To: Mike Gabriel <mike.gabriel@das-netzwerkteam.de>
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Hi,

To rule out some specific configuration issue in our current system, I installed a fresh linux mint inside a virtual machine and was able to confirm the issues.

You should be able to reproduce it easily by doing the same. Choose Linux Mint debian edition, 64 Bit, Mate package and install x2goserver following your instructions for debian 7.

With best regards,
David


Am 07.08.2013 um 17:56 schrieb David Fuhrmann <fuhrmann_mail@web.de>:

> Hi,
> 
> We are using a debian-based linux mint, and installed the server from the debian 7 repository IIRC.
> 
> I just tested at home on Ubuntu 10.04, and here it works fine. I think this might be some configuration issue.
> 
> Best,
> David
> 
> Am 07.08.2013 um 16:02 schrieb Mike Gabriel <mike.gabriel@das-netzwerkteam.de>:
> 
>> control: tag -1 - wontfix
>> control: tag -1 - not-a-bug
>> 
>> Hi David,
>> 
>> On Mi 07 Aug 2013 13:54:14 CEST David Fuhrmann wrote:
>> 
>>> thanks
>>> 
>>> ... for the answer. We just retested it today in our environment, and the
>>> issue is still as described. Especially we did:
>>> 
>>> 1) user_A starts a xfce x2go session on hostA, without starting
>>> x2godesktopsharing.
>>> 2) user_B logs in at hostA, using "connect to local desktop. It sees a X
>>> session under its own user name, and a port. user_B can click on "full
>>> access" and gets access to the session.
>>> 
>>> Second test:
>>> - user_A starts x2godesktopsharing, but leave the default setting (do not
>>> allow access, with cross).
>>> - user_B sees same behaviour as described above
>>> 
>>> Third test:
>>> - user_A starts x2godesktopsharing, but and enables access (green icon in
>>> menu bar)
>>> - user_B now sees two sessions in the session list: one with his own user
>>> name, one with user_As user name. Both have the same port. If user_B
>>> selects the one which has user_A as its name, he can only connect to view,
>>> and eventually, this connection gets refused. (In the mean time, user_A
>>> sees a question dialog asking user_B for access in the session.)
>>> But still, user_B sees a session with his own name, and can connect to it
>>> and gets full access to the xfce session started by user_A.
>>> 
>>> So in summary: The x2godesktopsharing has no effect at all when it should
>>> block all accesses, and only works partly when it should allow individual
>>> access.
>>> 
>>> In our environment, every machine has the same logins provided by an LDAP
>>> server. I will retest at home to see how it behaves with normal local users.
>> 
>> Ok, thanks for re-testing. I undo the taggings earlier made on this issue. This is indeed a big issue that needs immediate fixing!!!
>> 
>> Next question: what distro are you on. I tested on Debian and it worked flawlessly. Do you have any chance to test on Debian or Ubuntu (if you are on some RPM based distro)?
>> 
>> Greets,
>> Mike
>> 
>> 
>> -- 
>> 
>> 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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