Veras, 33, was 0-1 with an 8.10 ERA in 12 appearances after signing a one-year contract for $3.85 million with a $150,000 buyout.
Veras had a shaky spring training that carried over to the regular season. He lost the closer's job within the first 10 days and then went on the disabled list with an oblique strain. He was designated for assignment on June 3, and general manager Jed Hoyer said the team would try to trade him.
The Cubs will owe Veras the remaining portion of his contract, including the buyout.