A x2goclient regression update has been released for Debian GNU/Linux 8 LTS

Package : x2goclient
Version : 4.0.3.1-4+deb8u1
Debian Bug : 947129

A change introduced in libssh 0.6.3-4+deb8u4 (which got released as DLA
2038-1) has broken x2goclient's way of scp'ing session setup files from
client to server, resulting in an error message shown in a GUI error
dialog box during session startup (and session resuming).

For Debian 8 "Jessie", this problem has been fixed in x2goclient version
4.0.3.1-4+deb8u1.

We recommend that you upgrade your x2goclient packages.

Further information about Debian LTS security advisories, how to apply
these updates to your system and frequently asked questions can be
found at:   https://wiki.debian.org/LTS