Splitit <= 4.2.8 - Missing Authorization to Multiple Administrative Actions

The Splitit plugin for WordPress is vulnerable to unauthorized modification of data due to missing capability checks on several functions in the 'splitIt-flexfields-payment-gateway.php' file in all versions up to, and including, 4.2.8. This makes it possible for authenticated attackers, with Subscriber-level access and above, to change plugin settings, including changing the environment from sandbox to production and vice versa.