Bring chicken broth to a boil in a saucepan; stir couscous into boiling broth, reduce heat to low, and simmer until couscous is tender, 12 to 15 minutes. Drain couscous of any broth that did not absorb while cooking.
Stir couscous, cranberries, sunflower seed kernels, walnuts, and almonds together in a bowl.
Whisk vinegar, syrup, salt, and pepper together in a small bowl; drizzle over couscous mixture and toss to coat.
