In a small bowl, combine the olive oil, balsamic vinegar, dried oregano, dried basil, salt, and pepper. Whisk them together until well blended.
Peel the cucumber and score it lightly with a fork. Slice it thinly and dice it into bite-sized pieces. Quarter the cherry tomatoes and chop the red onion into small pieces.
In a large mixing bowl, add diced cucumber, quartered cherry tomatoes, chopped red onion, and fresh mozzarella cubes. Pour your prepared dressing over these ingredients and gently toss everything together until evenly coated.
Transfer your salad to serving plates or bowls. Chill in the refrigerator for about 10 minutes if desired. Serve and enjoy!