Yogurt sits in the maybe category. It is not automatically dangerous, but details matter.
Quick call
Usually yes, with caveats. Some dogs are lactose-sensitive, and flavored yogurt often contains excess sugar or xylitol.
What matters most
Plain, unsweetened yogurt only; always check label for xylitol.
When to call your vet
If your dog has vomiting, diarrhea, unusual fatigue, or belly pain after eating yogurt, call your vet the same day.
Source check: VCA and ASPCA both stress label checks for xylitol in sweetened products. Source