The score culminated an 18-play, 75-yard drive for the Cardinals (2-1, 1-0 MAC) after Buffalo (1-2, 0-1) took the lead.
Wenning completed 24 of 36 passes for 226 yards and two touchdowns. Jahwan Edwards ran for 112 yards and two TDs on 22 carries for Ball State.
Branden Oliver rushed 27 times for 118 yards and a touchdown for the Bulls. Buffalo trailed 21-7 but erased that deficit with the help of quarterback Chazz Anderson, who ran and passed for scores in the fourth quarter.
Anderson's 1-yard run ended a 14-play, 86-yard march that gave the Bulls a 25-21 cushion with 6:28 remaining.
Joey Counts scored on a 1-yard run on fourth-and-goal with 2 seconds left to give Montana a 38-35 victory over four-time defending FCS champion North Dakota State on Saturday.
Transfer Vernon Adams will be the starting quarterback when Oregon begins its season against Eastern Washington on Sept. 5.
Tim Beckman is threatening legal action after Illinois fired him as football coach Friday amid allegations of influencing medical decisions and pressuring players to play hurt.
LSU offensive coordinator Cam Cameron revealed in a post-practice news conference that he has been treated for prostate cancer but plans to coach this season.
The woman who accused former Baylor defensive end Sam Ukwuachu of raping her in 2013 has hired a Title IX law firm to represent her in potential civil litigation.
Arkansas tight end C.J. O'Grady has been arrested by Fayetteville police and charged with driving while intoxicated and being a minor in possession of alcohol.