CU confirmed that Moore is leaving the team and returning home "for personal/family reasons."
Moore, from Corona Del Mar (Calif.) High School, practiced with the Buffs through the first week of fall camp. He will not enroll in fall classes and CU said Moore "will likely transfer somewhere closer to home."
Moore missed all but three games of his senior year at Corona Del Mar because of injury.
In talking about the inside linebackers last week, assistant coach Ross Els said Moore was making an impression as a "very physical" player.
Moore was the only inside linebacker for the Buffs' 2018 recruiting class, although the Buffs do have true freshman Jake Yurachek as a preferred walk-on.
Moore's departure leaves CU with 82 scholarship players.
Contact staff writer Brian Howell at firstname.lastname@example.org or twitter.com/BrianHowell33.