The striker's tame looking volley from a Joe Anyinsah cross caught goalkeeper Jordan Archer unsighted and rooted to the spot.
The visitors contributed fully to an exciting game and went close on several occasions in the second half, including in a goalmouth scramble that proved the last action of the match.
Brunt had wasted Rovers' best early chance when shooting weakly at Archer from a low Fabian Broghammer cross.
Wycombe had begun brightly, but were unable to force a testing first-half save from Steve Mildenhall.
Both sides opened up after the break and former Rovers striker Jo Kuffour had two loud penalty appeals rejected.
The result made it six wins and two draws from nine games for Rovers since Ward replaced Mark McGhee as manager, but Wycombe will feel hard done by to have left with nothing.