The 34-year-old has been without a club since Milan released him at the end of last season but he could now be set for a move to La Liga.
According to Tuttomercatoweb.com, the Italian defender was reportedly in talks with Carpi but Spain now appears to be his most likely destination.
Bonera made 201 appearances for the Rossoneri in nine years but failed to ever get on the scoresheet.
Despite this he won the Champions League, a Serie A title and a Club World Cup with the team.
Villarreal are currently in the Europa League qualification places in La Liga after two games, which included a 1-1 draw away to Real Betis and a 3-1 win at home against Espanyol.
