#765 - Kex Error in X2Go client - X2Go Bug report logs

X2Go Bug report logs - #765
Kex Error in X2Go client

Date: Sat, 24 Jan 2015 12:55:02 UTC

Severity: normal

Found in version 4.0.3.1

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Message-ID: <CAN-5ny=PC8wpw1kd_pngVjXAB1J4tEZt2P37UprxfhKaVa8sfQ@mail.gmail.com>
Subject: Re: Kex Error in X2Go client
From: rpr nospam <rpr.nospam@gmail.com>
To: 765@bugs.x2go.org
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Hi! I also saw this issue while trying to connect with X2Go Client for Windows (v. 4.0.5.0) to x2goserver (v. 4.0.1.19-0~1064~ubuntu14.04.1) on a Linux Mint 17 machine. The connection worked fine until the SSH server on the Linux machine was reconfigured in order to harden it (see the recommendations in https://stribika.github.io/2015/01/04/secure-secure-shell.html). That reconfiguration allowed only the following host keys and key exchange algorithms: HostKey /etc/ssh/ssh_host_ed25519_key HostKey /etc/ssh/ssh_host_rsa_key KexAlgorithms curve25519-sha256@libssh.org,diffie-hellman-group-exchange-sha256 The Elliptic Curve Digital Signature Algorithm (ECDSA) (and the corresponding /etc/ssh/ssh_host_ecdsa_key) is not enabled because its implementation may use a faulty pseudo-random number generator (i.e. containing a back door created by NSA) as explained in some pages referred by the aforementioned article. After some investigation I found how to get rid of the error: in C:\Users\username\ssh\known_hosts remove the line corresponding to the x2goserver host and ecdsa-sha2-nistp256 key exchange algorithm: x2goserver_host_address ecdsa-sha2-nistp256 ... -- rpr.

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X2Go Bug report logs - #765 Kex Error in X2Go client

X2Go Bug report logs - #765
Kex Error in X2Go client