Apparently the default winter wolf picture has an earring?
6 magical beast HD, large size, the cold subtype, and pretty okay ability scores, but no opposable thumbs, reach, or interesting features. The few special attacks winter wolves have will probably end up not getting used, as two of them require using the bite (which is much better replaced with a mouthpick weapon) and the final one is just another of those blasting abilities so many monsters have.
Tiny skill bonuses and natural armor don't change that winter wolves are kind of meh. I'd assign them either a -0 or a +0, but will be going with -0.