Dallas selected the former Alabama star with a seventh-round pick in the 2018 NFL draft.
During the preseason, Scarbrough rushed 24 times for 69 yards and one touchdown.
In 31 collegiate games at Alabama, Scarbrough rushed for 1,512 yards and 20 touchdowns on 267 carries.
Scarbrough's reported release comes as somewhat of a surprise considering the Cowboys' lack of quality options behind starter Ezekiel Elliott.
With Scarbrough gone, the Cowboys will likely lean on Rod Smith, 2016 sixth-round pick Darius Jackson and utility man Tavon Austin as backups.
Dallas may look to keep Scarbrough as part of its practice squad, but the 6'1", 235-pound bruiser could be attractive to other teams in need of running back depth.