X2Go Bug report logs - #333
users can inject data into X2Go Client using .bashrc

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Package: x2goclient; Maintainer for x2goclient is X2Go Developers <x2go-dev@lists.x2go.org>; Source for x2goclient is src:x2goclient.

Reported by: "Dan Halbert" <halbert@halwitz.org>

Date: Mon, 21 Oct 2013 12:48:02 UTC

Severity: grave

Tags: confirmed, pending

Found in version 4.0.0.3

Fixed in version 4.0.1.2

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

Bug is archived. No further changes may be made.

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Subject: Bug#333: X2Go issue (in src:x2goclient) has been marked as pending for release
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Date: Tue, 29 Oct 2013 08:59:30 -0400
From: Dan Halbert <halbert@halwitz.org>
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To: Mike Gabriel <mike.gabriel@das-netzwerkteam.de>, 333@bugs.x2go.org
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Hi Mike, this fix to authenticate the commands is good. I didn't realize 
I was uncovering a security problem.

One question: the underlying crash was due to bad data. If authenticated 
but still bad data is sent, will the client still crash? I am thinking 
about a malicious server crafting something to crash the client or have 
it do something bad. I looked at the code diff and I didn't see some 
underlying verification of the x2go commands.

E.g.:
X2GODATABEGIN:<good-uuidhash>
bad data here
X2GODATAEND:<good-uuidhash>

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X2Go Developers <owner@bugs.x2go.org>. Last modified: Wed Dec 3 12:37:41 2025; Machine Name: ymir.das-netzwerkteam.de

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