Topic: Call for help to the forum's security experts - page 2. (Read 380 times)

...After you closed Firefox it may hang (with no UI) while some part of it is working... At least on Windows this is not uncommon.

Since I have no idea what can it be, I would start with doing changes that can help me find the culprit.
What if you use another browser for a while? It could be a test to show whether the problem is with your Firefox, some website or something else.
Also you can take a look what extensions you have installed, maybe you see anything suspicious.

These are 2 ideas/directions you can try.
And/or you can wait for answers from people more into Linux...

Thank you both. 

BlackHatCoiner (or anybody else): ask away. I'm ready. 

I haven't installed any program (other than electrum) for months. The computer is strictly mine, I have a 30 character password made of letters, numbers and signs. Literally speaking, this laptop has never been touched by anybody else but me, not even to wipe it off. I'm running Fedora 30 with Openbox and Tint2.
Right now, for example, after rebooting the computer, I'm typing this reply and seeing CPU usages of up to 50%, which is way too high for only using Firefox, especially on a forum.
I do have a lot of tabs open (mostly Binance, I'm checking prices), but haven't touched them since I restarted the machine.

NeuroticFish : well, I answered that question above...
A few months ago, there was a bit of a scandal because a customer found the ISP (Fibertel) was injecting malware in people's computers to mine crypto without consent (or knowledge). The company issued an apology, Starbucks issued another one, and they changed the ISP. But now (as in the last week or so, I've been coming to this store literally for months) I'm finding this problem.

I opened Firefox's task manager, but it's not showing anything out of the ordinary. Incidentally, what makes me even more suspicious is that I close Firefox and wait, and CPU usage stays near 100%. 

Fedora 30. Linux.


Does it happen always or it's related to visiting certain website? I'm asking because it was not uncommon, especially a couple of years ago, for websites to have crypto miners hidden in their pages.
You may want to take a look what does Firefox' task manager tell. Maybe it gives you a clue who's the culprit: https://support.mozilla.org/en-US/kb/task-manager-tabs-or-extensions-are-slowing-firefox

We can't know for sure if your laptop is affected with something malicious, but only make you questions to form a picture of your machine's status. Have you installed lots of programs whose reputation deflects their legitimacy? Is it yours, personal? Do you ever get to share it others? What's your OS?

I'm, as of now, using the wifi connection in a Starbucks store near my place. At least for now, that's the only option I have.
I'm running Fedora 30 (hope to upgrade soon), and using Conky as a system monitor. For the last few days I've been seeing my CPU usage go through the roof for no reason, so I'm suspecting my laptop is being used to mine crypto while I'm working (there was a reported incident not long ago for the same company).
Normally, my CPU usage hovers around 5%. The absolutely HIGHEST I've seen it go was about 30-35% when I was running Freecad and VLC at the same time. Right now, I'm seeing CPU usage in the upper 90% only on Firefox, which makes no sense.
Memory usage seems to be ok though, at around 15%.
I ran ClamAV, and, unsurprisingly, didn't find anything.
Should I be worried?
What can I do about it?

Thank you  all in advance.