Colbert has a strong chance at playing time given Miami just put two of its starting safeties on injured reserve.
The Dolphins also activated LB Andrew Van Ginkel, who had previously been designated to return from injured reserve.
Colbert, 25, is a former seventh-round pick of the 49ers back in 2017. He was in the second year of his four-year, $2.48 million contract when the 49ers placed him on injured reserve coming out of the preseason.
San Francisco later waived Colbert with an injury settlement and he signed on to the Seahawks’ practice squad. He’s been on and off Seattle’s practice squad this season.
In 2018, Colbert appeared in seven games for the 49ers and recorded 21 tackles, no interceptions and a pass defense.
Van Ginkel, 24, was selected in the fifth round by the Dolphins back in April. He signed a four-year, $2,831,964 contract with the Dolphins that included a $311,964 signing bonus.
Van Ginkel stands to make base salaries of $495,000 and $585,000 over the first two years of the agreement.
During his college career at Wisconsin, Van Ginkel recorded 98 tackles, 12 sacks, two interceptions, a defensive touchdown, four forced fumbles, a recovery and five pass defenses over the course of two seasons and 26 games.