cannot open youtube, google and facebook?

[Freddy K]

I got this grey screen with notification in the middle that said "WARNING! Your Flash Player may be out of date. Please update to continue" and if i click ok, it opens a download page for Flash Player, but its not from adobe.com

I suspect that its some kind of malware, but i did a full scan with Malwarebytes and Avast Antivirus but it didn't catch anything. I evn did a boot but didn't find anything either.

Today I can access google and facebook, but youtube still shows the same screen.

I updated my Flash Player from adobe... no changes. I've tried using https too, not working. Safe mode on firefox and private window didn't solve it. I can't find anything suspicious in my plugins. Tried chrome and IE, same results...

Did anyone else had the same problem?