Subject: Filter ACPI events

From: Yetoo <[email-masked]>
Date: Tue, 25 Apr 2023 10:28:14 -0700

Package: x2goserver
Version: 4.1.0.3-5
Severity: Critical

I have x2goclient installed on local Fedora 37 machine and
x2goserver/x2godesktopsharing installed on remote Debian 11 and
(different) Fedora 37 machines. On the Fedora 37 local machine I
connected to the Fedora 37 remote machine in X2go/X11 Desktop Sharing
mode with fullscreen and press the power button on the local machine.
This causes the Fedora 37 remote machine to respond to the shutdown
command as configured and, in this instance, shutdown. I tested with a
Debian 11 remote machine with x2goserver/x2godesktopsharing installed
on it and it too responded to the shutdown acpi command. Both remote
machines have xfce4 desktop installed.

I expect the server to at least discard ACPI events and not depend on
a client to not send ACPI events. For thin client users expecting the
machine to be separate from the software in the remote connection this
increases chance of unintentional user error messing up data or even
malicious abuse.

Client packages:
x2goclient 4.1.2.2-7.f37
Package nx-libs 3.5.99.26-5.fc37
Package nxproxy 3.5.99.26-5.fc37

Debian 11 remote/Server packages:
x2goserver 4.1.0.3-5

Fedora 37 remote/Server packages:
x2goserver-4.1.0.3-19.fc37