I think Punk is the only guy that actually beat Cena consistently, and MAYBE Edge. Besides that everything he's involved in is always one sided to his advantage.
Rocky laid him out on PPV for over 2 years
Lesnar has only lost once to him
Taker has beat him all but twice I think
Angle used to always beat him until fall 2005
Eddie beat him all the time except once
Punk beat him or had multiple draws with him from 2011 till he left
Bryan beat him clean as fukk at Summerslam 2013..got away with spitting in his face too with no repercussions.
Federline is undefeated against him