Yarbrough signed with the San Francisco 49ers on Monday, Doug Kyed of Pro Football Focus reports.
Yarbrough had two total tackles and QB hit in Sunday's loss to Green Bay.
Yarbrough was signed by the Vikings off the Bills' practice squad Tuesday, Field Yates of ESPN reports.
Yarbrough signed a one-year contract with the Bills on Wednesday, Vic Carucci of the Buffalo News reports.
The Bills extended a tender to Yarbrough, an exclusive rights free agent, Mike Rodak of ESPN.com reports.
Yarbrough signed his restricted free agent tender with Buffalo on Monday, Chris Brown of the team's official site reports.
Yarbrough won't practice Wednesday due to an unspecified injury, Sal Capaccio of WGR Sports Radio 550 reports.
Yarbrough's teammate Shaq Lawson was placed on injured reserve Tuesday due to an ankle injury.
Yarbrough (chest) is listed as active for Sunday's tilt against the Patriots.
Yarbrough (chest) was limited for the second straight practice Friday and is listed as questionable for Sunday's game against the Patriots.