Mosquitoes are drawn to the scent of limburger cheese and its derivatives. They love it so much that it can even lure them away from tasty human targets. Why? For a reason you don't want to know if you plan to eat limburger cheese ever again.
Mosquitoes crave human blood. And limburger cheese. What is the common factor between them? Not a damn thing, because mosquitoes don't lap up a pool of blood on the floor. They go after flesh, particularly moist and relatively insensitive flesh. Foot flesh. (Incidentally, vampire bats also tend to go after the feet. Most people who have been bitten by bats have been bitten on the toe.)
The human foot and the limburger cheese do have something in common - a genus of bacteria. Brevibacterium epidermidis is the stuff that crawls around between your toes, stinking your sock up. Brevibacterium linens is a type of "smear bacteria," the bacteria that produces the rind on soft, smelly cheeses. It can't survive without oxygen, so it only grows on the surface of cheese. It also needs a moist and salty environment, and since cheeses don't produce foot sweat cheesemakers have to wash these cheeses with water to keep them wet. This is why they're called "washed rind cheeses." On the moist cheese, the B. linens chew through proteins to produce volatile fatty acids, which is the stuff we might not love to smell but that we do love to eat.
The Brevibacteria on feet also dine on proteins in a moist, salty environment, producing a smell that lets mosquitoes know they're close to something they love to eat. Perhaps they object to the smell as well. According to a paper in the Lancet, "gaschromatographic analysis of toenail scrapings and limburger cheese odour have shown strong similarity in their carboxylic fatty acid composition." In other words, both we and the mosquitoes are going after our foot funk.
There are all kinds of bacteria that can be used to make cheese, which leaves people puzzling over why we crave the smell of our own feet (and yes, armpits). If only we could ask the mosquitoes.