Garafolo mentions that Carroll has been dealing with a concussion and rookie Jourdan Lewis has stepped up in his absence.
Carroll, 30, is a former fifth-round pick of the Dolphins back in 2010. After four years in Miami, Carroll signed on with the Eagles in 2014 before returning to Philadelphia on a one-year, $2.36 million contract last year.
The Cowboys signed him to a three-year, $10-million contract that included a $3 million signing bonus this past March.
According to OverTheCap.com, releasing Carroll will free up $3 million of available cap space while creating $1 million in dead money.
In 2017, Carroll has been limited to appearing in two games and recorded five tackles and no interceptions.