Need help understanding what caused a weird security issue
I came home from work and my roommate shows me a picture of a text he got from one of his classmates. He's has a few of them over to study and they have brought their laptops. Most of them use my Wifi and it's never been an issue. The picture was a screen shot of my user name (same of this one) for my login of my Gmail account. Apparently she has been able to get into my email. How, I do not know. I can't even just log into my email on any computer, I always at least have to enter the password. She also was using Google Chrome and had all of my bookmarks. and all my Extensions. How could this happen? This girl knows very little to nothing about computers so the hack-ability of her doing something is no-existent.
I finally convinced her to let me use Teamviewer to remote in. I cleared all her extensions including Xmarks. I deleted all her (I mean my) bookmarks and cleared all her cookies, temp files and active logins.
Question is, how the hell did this happen? I assume she had a virus and when she was on my Wifi it managed to get on my network, but how did it completely copy my Google Chrome verbatim? Should I be worried about anything else?
We both are on Windows 7.
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