Yes. To be clear, "infantry" and "cavalry" aren't a thing in itself in TOW as it used to be in Fantasy;
Infantry for instance, is divided into "Regular / Heavy / Monstrous".
A rule that works against (or works if you are) "Infantry" will work regardless if you are regular infantry, heavy infantry or monstrous infantry, and same goes for cavalry and it's sub categories.
So KB works against anything except Chariots, Monsters and Warmachines iirc.