A media flow transport security manager of a hybrid cloud-based media production system having a network orchestrator and an extensible resource manager (ERM) includes a firewall communicatively coupled to a computing platform having a hardware processor and a memory storing a security software code. The hardware processor executes the security software code to communicate with the network orchestrator to identify multicast production media flow(s) for processing in a cloud-based virtual production environment, and to communicate with the ERM to obtain an identifier of each cloud-based resource used for processing cloud production media flow(s) corresponding to the identified multicast production media flow(s). The hardware processor also executes the security software code to receive an alert that the cloud production media flow(s) have been processed to generate corresponding post-production cloud media flow(s), and to route, using the obtained identifier of the cloud-based resource(s), the post-production cloud media flow(s) through the firewall.