Im gettin sued from a third party, for supposedly downloading/uploading an illegal movie?

some shady lawyer sent the court civil order to comcast, comcast sent it to me, got viruses on my computer, who knows what i clicked by mistake causing some downloading of something, plus 3 other people in my house use this internet service, i need to quash or vacate the subpoena, or comcast will give out my info in 30 days to them, i cant find much info on the term quash, has anybody dealt with this before? I looked into the guy suing me, seems like its entrapment and extortion, as i am including upon hundreds gettin sued. Another question, if i cancel comcast services could they still give out my info? just looking for some advice, free of course, im broke haha, anything would be most appreciated.