I'm the first one to admit this, some of my paranoia might be unjust. Some I haven't really bothered to think of why I'm feeling the way I do about, and as long as I don't have to run them I don't really bother to look into it.
Only rule, no systemd because we don't need another of those threads.
* Electron
No idea why really. I just have this feeling that it will blow up some day and be the next Heartbleed.
* WordPress
It's so popular so people will always try to find new exploits in it. If I have to use it I prefer to run it in a container, on a different computer, in another room, preferably without internet connection.
* Anything Facebook/Google/Microsoft
It might have nice feature and all but their main goal is to earn money out of your surfing habits so they will use it in some way you didn't think they'd use it.
* Node.js
What I've heard its dependency hell and I feel a bit paranoid whenever people download things from the net without checking it for harmful code. Even containers break sometimes.
* Telegram messenger
Sorry, but the whole thing with closed source servers rub me the wrong way. Feels like the authorities just are waiting for The Reason to break it and log everything.