Taliban don’t fall in the category of Khawarij. Khawarij by rule are those who do takfir on companions of Prophet s.a.w.
I believe Aashura blast was not work of Taliban, as they are not stupids to send just one suicide bomber killing 40 people. Aashura processions had hundreds of people, if Taliban attacked they would at least kill 200 to 300 people in such a big gathering. I say that because following Aashura almost 100 people were killed in Laki Marwat by 3 suicide attackers who blew up their vehicle. Did you see the suicide bomber sent by Taliban in Aashura blast? No you didn’t. Now please stop misleading people because of your hatred for Taliban simply because of sectarian reasons. I also hate such Taliban not because of their faith, but because of their actions.