Problems with the mask are a defect in CSW – the standard clearly says that having a barely pronounced mask is a fault.
This is a fault – not a disqualifying fault! You can certainly work and breed a dog with a weak mask, though not ideal there are many reasons to do this, if the dog has other desirable characteristics – It is very rare to find a “perfect” wolfdog. (Even if someone found a perfect wolfdog, someone else would not agree it was perfect…)
There are two possible faults with the mask. One is the so-called black mask, where the mask of the dog is poorly defined because the muzzle is too dark (ie similar to a German shepherd) this is probably one of the most common faults amongst CSW. It is not generally considered serious (unless the muzzle is pitch black!) but such a dog would be unlikely to obtain good results in dog shows, especially in the countries of origin.
A second, rather less common fault with the mask is from dogs that have a mask that is too white – and again is poorly defined. This is rather rare though I have seen some dogs that could be considered to have a weak mask because their muzzle was simply too lightly coloured.
The two bonitation codes associated with mask problems are M2 (without mask) and M5 (not expressive mask) note that neither of them refer to the mask being white or black – just being adequate or not.
The mask in wolves is both a means of expression (it needs to be defined) but also as a means of camouflage (the colours need to blend, and not form sharp lines) this is really what is most desirable in the CSWs as well.
You may want to look at
this article for more information on the bonitation codes, very informative as to what is judged in a wolfdog.
J.