Competition for places
The 22-year-old has been on trial with the Terriers and played in three of the last four matches of pre-season, including a full 90 minutes in the 1-0 win over Barnsley.
With Martin Cranie suffering a hip injury that could keep him out of action for up to eight weeks, manager David Wagner is looking for a new right-back to give Tommy Smith some competition for a place in the starting XI.
Town are set to embark on their first-ever Premier League season with a visit to Crystal Palace on August 12.
Wagner has wasted no time in the transfer market
The Huddersfield boss has added no fewer than nine signings to his squad this summer and Cavare looks set to be the tenth addition.
Wagner is a fan of rotating his squad, as shown throughout last season as the West Yorkshire side achieved promotion through the playoffs, and the Frenchman must have done enough to impress during his trial period.
Capped at France U20 level, Cavare began his career with Lens progressing through the B side to the first team before leaving for Rennes in a £2.7m deal in February 2015.
He was allowed to stay with the Stade Bollaert-Delelis side on loan for the rest of the 2014/15 season only to suffer a cruciate ligament injury just weeks later in a 2-0 loss against Evian.
The injury kept him out of action for over a year and he made just five appearances last season in all competitions for Rennes.
Should the move go ahead, Cavare will likely to play back-up to Smith who was a key player in Town's promotion-winning squad last season scoring four goals and creating a further eight.