Mahlangu has signed a contract to the end of the season with an option to renew having not played any competitive football since leaving Turkish side Konyaspor in June.
“The 26-year-old central midfielder passed medical tests earlier today [Monday] and is now officially a Canary,” the club said in a statement, alluding to their nickname.
Mahlangu joins compatriot Benni McCarthy at the club with the former Bafana Bafana star acting as assistant coach to Northern Irishman Chris O'Loughlin, who was once on the technical team at Orlando Pirates. Mahlangu last played for Bafana Bafana against Angola in June