AVideo: Arbitrary Stripe Subscription Cancellation via Debug Endpoint and retrieveSubscriptions() Bug

WWBN AVideo is an open source video platform. In versions 26.0 and prior, the StripeYPT plugin includes a test.php debug endpoint that is accessible to any logged-in user, not just administrators. This endpoint processes Stripe webhook-style payloads and triggers subscription operations, including cancellation. Due to a bug in the retrieveSubscriptions() method that cancels subscriptions instead of merely retrieving them, any authenticated user can cancel arbitrary Stripe subscriptions by providing a subscription ID. At time of publication, there are no publicly available patches.