Benzema netted either side of half-time after Ribery had opened the scoring following a fine one-two with the striker as Les Bleus stretched their unbeaten run to 21 matches.
Winger Jeremy Menez completed the rout in stoppage time.
"It's important to gain confidence, it's important for the strikers to score goals but, despite the scoreline, I think the team were not as good as against Serbia [a 2-0 win in their last friendly]," coach Laurent Blanc told French TV channel TF1.
"We were not good in defence. We need to play it more simple at the back. We are like the other teams, we hope to be ready on June 11," he added referring to their opening match against England in Group D being played in Donestsk, Ukraine.
After full-back Patrice Evra produced a miserable performance in a 3-2 win against Iceland in their first of three Euro warm-up games, it was Philippe Mexes's turn to raise concerns.
Laurent Blanc's side went ahead in the 25th minute when Ribery chested down a Benzema pass just inside the box before firing past Sergei Pareiko with a cross shot.
Seven minutes before the break, Benzema sent a curling shot into the far corner of the net to double the tally and scored his 15th goal for France by latchig onto Ribery's cross from the right.
