Here are the ingredients for Nabisco Nilla Wafers:
UNBLEACHED ENRICHED FLOUR (WHEAT FLOUR, NIACIN, REDUCED IRON, THIAMINE MONONITRATE [VITAMIN B1], RIBOFLAVIN [VITAMIN B2], FOLIC ACID), SUGAR, SOYBEAN OIL, HIGH FRUCTOSE CORN SYRUP, PARTIALLY HYDROGENATED COTTONSEED OIL, WHEY (FROM MILK), EGGS, NATURAL AND ARTIFICIAL FLAVOR, SALT, LEAVENING (BAKING SODA AND/OR CALCIUM PHOSPHATE), EMULSIFIERS (MONO- AND DIGLYCERIDES, SOY LECITHIN). CONTAINS: WHEAT, MILK, EGG, SOY.
I think it looks Halal-ok. Unless I'm missing something....