An apparatus is provided that includes a processor configured to receive a captured traffic unit (CTU) intended for a network service, the CTU being one into which incoming traffic has been assembled based on a filter describing which incoming traffic to capture and how to assemble the respective incoming traffic into the CTU. The processor is also configured to determine whether to allow the CTU to pass to one or more applications configured to implement the respective network service based on a passlet including permissions to a particular user. The processor is further configured to instruct a firewall to allow the CTU to pass to the respective one or more applications or to reject the CTU based on the determination. In this regard, the processor is configured to perform the above functions under control of a security framework implemented in middleware between a user-level domain and a system-level domain.