The Black Cats took the lead when Corry Evans opened the scoring with a low shot in the 16th minute, yet U’s defender Elliott Moore headed the hosts level before half-time.
Both sides had chances in the second half before Sunderland substitute Elliot Embleton scored a dramatic winner two minutes from time.
The result moves Sunderland back up to sixth in the League One table with five games remaining.
Our chief SAFC writer Phil Smith has delivered his verdict on how each Black Cats player fared at the Kassam Stadium:
The result moves Sunderland back up to sixth in the League One table with five games remaining.