Heartbleed isn't new either. It's from years ago. It's also unrelated to the xz backdoor. Maybe you should get some rest. Check your carbon monoxide alarms are working. If not see a doctor. It sounds like you are having memory issues.
Still paniking, cause the backdoor was apparently targetting Debian servers, it was discovered just by chance and the "mantainer" made commits for 2 years in the same repo
and it was only discovered accidentally, when someone was profiling some stuff, noticed SSH using a bit too much CPU power when receiving connections even for invalid usernames/passwords, and spent the time to investigate it more deeply. A lot of developers aren't that attentive, and it could have easily snuck through.
