Edit: A better view of the third guy hitting Punk.
Better view of it here, embedding is disabled so you have to watch it on YouTube.
Punk runs into the crowd to stare angrily at Vince McMahon in the ring. One fan pushes him and another accidentally bumps him. A third fan pushes so Punk has enough and strikes the guy behind him a few times so people can get the hint. I don’t blame Punk for his actions but it’s a shame the guy who was doing it accidentally became the recipient and not the other guy.