Note the other thread on temperament. It was a known fact many years ago that Basenjis would bite first, ask questions later.
I hear this from time to time and smile. My first Basenji that I had in 1966 had the best temperament of any of them. She was absolutely fine with anyone and everyone, loved children, was aloof but not snarky with adults, and I could take her anywhere. My Mom took her on a Humane Society tag day, lots of strangers patting her and when one picked her up she yodeled! If I disturbed her when she was sleeping, she would grumble, and if I picked her up when she was comfortable she would snarl…...sounded like a fire engine.....but she would never nip or bite.
I have never known a Basenji that wouldn't snark if you disturb them when they are comfortable, but most of mine were all noise, no action.
Like most breeds, there are good and bad. I think one reason people get the impression they are nasty is that most Basenjis will stand on their dignity and don't suffer personal disrespect gladly. You generally can't take liberties with one that doesn't know you.