I WOULD SAY THAT KURDISTAN IS SAFE FOR BACKPACKERS
Kurdistan poses very little problem. It is probably as safe as any developing country.
Beware though, the country has very high standards for living, but the evolution of the social structure is still low.
They operate on some strong religious and cultural taboos. It may appear they do not care. But they do.
I would say that Mosul is still for only the most season traveler, but soon OK.
Women should probably not come alone.