Hack tool has been detected (1) 0:5:0:0

Hello, This is the second time this has happened to me, and since the first time it happened to me was in the middle of a match, this time it wasn't so I was able to capture the screenshot, I cropped it out of my desktop since it was in windowed mode so you'll see a bit of a border from my desktop background, ANYWAYS, I was playing normally the first time, and out of nowhere I get that message, and when I try to log back in I had a short ban. I didn't understand and got rather mad since I have never hacked an online game involving other live players in my life, because I hate unfair play between others. Now, the second time, I WASN'T EVEN PLAYING THE GAME! I was literally alt-tabbed looking at my browser, and this message popped up (screenshot linked below). I have no reason to hack, I don't need cheats to play against other players, that's just ridiculous. I don't want to get randomly banned from a glitch and for playing the game normally. Please fix this.

Screenshot:
http://imgur.com/FSqYJaE