Leinster are hopeful the Ireland and Lions internationals will be fit to face Ulster in next Saturday's European showpiece at Twickenham but no official diagnosis has yet been announced.
"Rob Kearney (back) and Brian O'Driscoll (knee) picked up niggles in training this week and have been ruled out for this weekend's game," read a Leinster statement.
"The Ireland duo will be further assessed by the Leinster medical team over the coming days."
O'Driscoll, who skippered the Lions in 2005 and also toured in 2001 and 2009, only returned to action ahead of the crushing quarter-final win over Cardiff Blues having missed all six of his side's pool games with a neck and shoulder injury.
The 33-year-old Ireland captain has been an inspirational figure for the Dublin-based province since making his Heineken Cup debut in the 1999/2000 season.
O'Driscoll has played 77 games in the tournament and scored 31 tries in the process, picking up winners medals in 2009 and 2011, and his absence would obviously be a huge blow to the reigning champions.
Kearney, who was a Test Lion alongside O'Driscoll three years ago, suffered Heineken Cup heartbreak last season when he was forced to sit out the final through injury.
The 26-year-old has been Europe's form full back so far this season, featuring in all eight of Leinster's games so far and scoring an impressive six tries along the way.