Silva has not competed at 205 pounds since December 2008, when he was knocked out in the first round by Quinton "Rampage" Jackson.
A former PRIDE middleweight (205 pounds) champion, Silva has a professional record of 34-12-1 with one no contest.
The fight with Stann will be Silva's first since June 23, when he was on the short end of a unanimous decision to Rich Franklin. That bout was contested at a catchweight of 190 pounds.
Stann, a former WEC light heavyweight champion, made his middleweight debut in August 2010 – submitting Mike Massenzio in the third round.
Stann made it clear that his return to light heavyweight is temporary.
"I'm not moving to light heavyweight, just one fight," Stann said on Twitter. "(I) couldn't find a matchup at 185. Everyone is matched up or hurt in (the) top 10 and Wanderlei doesn't want to cut."
Stann (12-5) will seek to rebound from a unanimous decision loss to Michael Bisping on Sept. 22 at UFC 152.