Bring a large pot of water to a boil over high heat. Add ears of corn to boiling water and boil 5 minutes. Drain and pat dry. Use a sharp knife to cut the kernels from the cob and place into a large mixing bowl.
Toss corn with tomatoes, cucumber, avocado, onion, basil, and mint.
In a small bowl, whisk together cider vinegar, red wine vinegar, olive oil, salt, and pepper.