Flynn's agent, Bill Johnson, confirmed the two sides had agreed to terms. Details were not announced.
Flynn threw for 1,146 yards with seven touchdowns and four interceptions in five games in 2013 with Green Bay, including four starts. Flynn helped lead the Packers to two December victories following a five-game winless kid coinciding with Rodgers' injury.
Flynn also spent time with the Raiders and Bills last season before returning to Green Bay, which drafted him in the seventh round in 2008. ESPN and NFL Network first reported Flynn's signing.
The Packers also have Scott Tolzien behind Rodgers and Flynn at quarterback.
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