Bring a large pot of salted water to a boil.

Add the spaghetti to the boiling water and cook according to package instructions until al dente, about 8-10 minutes.

Once cooked, drain the spaghetti in a colander and rinse under cold water.

While the pasta cools, chop the cherry tomatoes, cucumber, bell peppers, and red onion.

In a large mixing bowl, combine the cooled spaghetti, chopped vegetables, black olives, and mozzarella cheese.

In a small bowl, whisk together the olive oil, red wine vinegar, Italian seasoning, salt, and pepper.

Pour the dressing over the salad mixture and toss well.

Cover the salad and refrigerate for at least 30 minutes before serving.