These are not a real danger to your dog in that there is no system that will be affected in a toxic manner. They can, however be difficult to digest for dogs and are not advised. Mild gastrointestinal distress may occur but is not a threat.
There is the possibility of a mold being on the nuts, Aspergillus which can produce the poison Aflatoxin. This is measured safe by the FDA for human consumption but dogs are very sensitive to this toxin, which causes hepatocellular necrosis.
Nuts also have a high level of phosphorus content that can cause bladder stones.