How to defuse XZ Backdoor (or alike) in SSH Daemon
XZ Backdoor in SSH Background Someone planted a backdoor in XZ compression, which is believed to affect SSH. More details can be found. Although it was never shipped to production version of any distro. Even if you are using unaffected version I suggest you defuse any similar backdoors. https://www.openwall.com/lists/oss-security/2024/03/29/4 https://news.ycombinator.com/item?id=39865810 https://gist.github.com/thesamesam/223949d5a074ebc3dce9ee78baad9e27 https://www.redhat.com/en/blog/urgent-security-alert-fedora-41-and-rawhide-users The Kill Switch The backdoor has a kill switch, it does not activate if it detects that someone is observing it (debugger attached...etc). An easy way to defuse the backdoor is to just define TERM environment variable causing the backdoor to think it's being observed and it would disable itself hopefully this is not specific to this backdoor but any similar one. mkdir /etc/systemd/system/sshd.service.d/ echo -e "[Service]\nEnvironment=TERM=xt...