Quick fix for these types of issues. Change your Email password and run your antivirus. They did not get your pass but they got your Hash for your pass and are using it to send emails to your contacts. Since this happened to me I removed my contacts and save them in Excel so even if I do get hacked there is not contact list for them to spam.
They got me, too. But I don't keep a contact list. (and this is why)
but somehow they were sending emails to people I haven't contacted
in years. Some only once. And that info is not on my computer.
I know these sites keep info and share it. Pee pees me off. Every month
LinkedIn asks me if I know so-and-so .. someone I emailed ONCE about
5 years ago because he was selling something on CraigsList. And I
didn't email him through LinkedIn..
And if I want to respond to a story on Yahoo News, it tries to use my
Facebook login. If I decline that, Yahoo logs me out of Facebook!
and these companies wonder why some of us use ad blockers and
script blockers.. 90% of the websites I go to won't show me much
because of the sheer number of scripts that get blocked. I remember
once counting scripts for 18 different companies I've never heard of
just to check my email..