X2Go Bug report logs - #1003
x2goclient sshd (for folder sharing) weak host key

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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: Florian Wicke - Hetzner Online GmbH <florian.wicke@hetzner.de>

Date: Thu, 25 Feb 2016 15:20:01 UTC

Severity: normal

Tags: pending

Fixed in version

Done: X2Go Release Manager <git-admin@x2go.org>

Bug is archived. No further changes may be made.

Full log

Message #5 received at submit@bugs.x2go.org (full text, mbox, reply):

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To: submit@bugs.x2go.org
From: Florian Wicke - Hetzner Online GmbH <florian.wicke@hetzner.de>
Subject: x2goclient sshd (for folder sharing) weak host key
Message-ID: <56CF1213.9080407@hetzner.de>
Date: Thu, 25 Feb 2016 15:39:15 +0100
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[Message part 1 (text/plain, inline)]
Package: x2goclient

The sshd (sshd.exe) spawned by x2goclient for things like the folder
sharing is creating a DSA HostKey.

Even if this sshd is only listening on localhost and is accessed through
the ssh tunnel from the X2Go server this might lead to connections
errors if the ssh_config of the server is configured to not allow
connections to these weak (1024 bit) DSA HostKeys.

I would advice increasing this to at least 2048 bit RSA host keys or
even elliptic curve host keys if available.

Best regards,

 Florian Wicke

Hetzner Online GmbH
Industriestr. 25
91710 Gunzenhausen
Tel: +49 9831 505-187
Fax: +49 9831 505-387

Registergericht Ansbach, HRB 6089
Geschäftsführer: Martin Hetzner

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