The 29-year-old has arrived at Pittodrie on loan from the midlands club until the end of the season, with a view to a permanent deal when his contract runs out at the end of the season.
The full-back had been training with former club Hearts, fuelling rumours he was on his way back to the club.
But Dons boss Jimmy Calderwood stepped in and managed to beat off other interested parties to his signature.
Maybury is a product of the much-vaunted Leeds United youth system that also saw the likes of Alan Smith, Aaron Lennon, Scott Carson, James Milner and Paul Robinson come through. He can play at right and left back as well as in midfield, very much like Jimmy Calderwood's last signing Stuart Duff.
The experienced full-back, who has 10 caps for the Republic of Ireland, will strengthen the squad after the departure of Michael Hart to Preston for around £100,000, as reported on Aberdeen-Mad last week.
Meanwhile, Dons youth players Stuart Smith and Neil 'Hob Nob' McVitie have joined Neale Cooper's Peterhead on loan until the end of the season.
And Michael Paton, who is on loan at Brechin City and was at the heart of the club's expulsion from the Scottish Cup, has extended his loan period until the end of the season.
As a result of Brechin's Scottish Cup ejection, Aberdeen will now play Hamilton Accies at Pittodrie in the cup on Saturday after the fourth-round game was initially postponed.