What are the worst blunders ever committed in a world championship match (final)? As title above, what are a few of the worst blunders ever committed in a World Chess Championship Match?
By far, the biggest blunder in all world championship is absolutely 32.Bb4?? played by Chigorin in the 1892 match. He threw away the win and the match, landed himself to mate in 2.

https://en.wikipedia.org/wiki/World_Chess_Championship_1892
A piece up, Chigorin should have won after 32. Rxb7 (32...Rxd5? 33. Nf4 forks the black rooks).[1] Instead the game and match ended suddenly when Chigorin blundered with 32. Bb4?? Rxh2+ White resigns, as Black will mate on the next move.[1][3]