Pure hydrogen peroxide will do a lot worse than burn on contact with an open sore, unless you mean "set your sore on fire" (though it's more likely to detonate, or spontaneously dissociate into steam and pure oxygen).
Usual solutions for disinfection are 3~5%, at 35% h2o2 will bleach skin, and bite through it.
Read up on the Me-163 if you want to see the craziness that's involved with using high-purity H2O2 as an oxidizer. With a hydrazine/methanol mix fuel to boot.
30% is non-chlorine pool shock, and readily available where I am (VT). As it happens, it's also one of the parts of two part wood bleach. The other part is a solution of NaOH (lye, available in solid form for drain opener). Works great, best used while wearing gloves and a face shield.
Usual solutions for disinfection are 3~5%, at 35% h2o2 will bleach skin, and bite through it.