Cook the pasta in salted boiling water according to package directions until al dente. Drain and rinse under cold water to stop cooking; set aside to cool.
While pasta cooks, prepare the vegetables: halve cherry tomatoes, dice cucumber and bell peppers, thinly slice red onion, slice olives, and chop parsley.
Make the dressing: In a small bowl or jar, whisk together olive oil, red wine vinegar, lemon juice, Dijon mustard, minced garlic, dried oregano, salt, and pepper.
In a large mixing bowl, combine the cooled pasta, all prepared vegetables, and parsley. Pour the dressing over the salad and toss until everything is evenly coated.
Cover the bowl with plastic wrap or a lid and refrigerate for at least 30 minutes to allow flavors to meld. Serve cold or at room temperature.
