Even check those "really old backup" for malware.really old backup use it. Even better
Not really. Many of my attacked sites have never returned to normal.Good news, once you clean it, everything will be back to normal.
Do you think malware goes only through plugins or it can be affected if SSL was disabled?Not really. Many of my attacked sites have never returned to normal.
But I have to admit it took me a while to take action over them on a period I did not have time to manage such attack
I think that the sooner you act, the better. Google nowadays is much faster taking decisions on the condition of a site. I remember that some years ago, a 404 for months would not have any impact if you recover it after a while. Nowadays, a 404 can go completely deindexed and removed from all searches in barely some weeks.
I doubt that SSL was relevant at all, unless they did a MITM when you were login in your site, and got your credentials in plain textDo you think malware goes only through plugins or it can be affected if SSL was disabled?
Can you send me PM with detailsThis had an impact on a lot of my peers. There are some experts who can assist you in handling this effectively.