I very much doubt that this is even anywhere close to the level of xz. If, big IF, this is some kind of backdoor, then whoever made it didn't put nearly as much effort into hiding it as they did with xz and it would've probably been found already.
No, of course not.
I'd never run any service as root unless it's absolutey necessary.
I'm actually still baffled by this because I have no idea how this could happen.
A friend of mine suggested that Librewolf may have edited my ufw rules, but unless my understanding of how file permisions in Linux work is fundamentally flawed (without me ever running into problems because of it) that shouldn't be possible. Especially because ufw status still shows the IP as denied.
I'm thinking about filing a bug report to ufw about this.
Then why was netstat showing an active conection to this server at all times?
Seems that way, as I have not given any website permission to send me notifications.
It seems to be a Mozilla server though, which is just hosted by Google. In my book that doesn't make it much better though.
That seems to have solved it, thank you.
I completely forgot about the Librewolf FAQ.
I still don't understand how it got through the firewall though.
I was monitoring my network traffic when I noticed that Librewolf was constantly connected to the IP 34.107.243.93.
A quick search made me find this post https://support.mozilla.org/en-US/questions/1364193 on the Mozilla Support Forum, according to which Firefox is constantly connected to the IP 34.107.221.82 to check for an internet connection, so I assumed that this connection had a similar purpose.
The problem I have with that is, that dig -x 34.107.243.93 returns 93.243.107.34.bc.googleusercontent.com. As I didn't like the idea of my computer being connected to a google service whenever I use Librewolf, I tried deactivating the connection or at least changing the IP, but I couldn't find a feature for this in neither the settings nor the about:config.
I tried blocking the IP with UFW, but the the connection still exists even after restarting the browser or rebooting. I have three questions:
A: Am I correct in the assumption that this connection exists to check for an internet connection or is something else going on here?
B: Is there a way to deactivate this "feature" or at least change the IP to that of a more privacy respecting party?
C: How can the connection persist after I blocked it in my firewall? I haven't tried blocking it in my router yet, but I find this really creepy.
I've enjoyed using Librewolf for almost 3 years now but this is really bugging me.
I'm thanking you in advance any replies and advice.
EDIT: Accidentally wrote "browser" instead of router in question C.