1. A method for protecting a virtual machine network, the method comprising: storing an application whitelist specific to a hypervisor within the virtual machine network in memory of a host machine, wherein the application whitelist is used to determine whether applications are permitted to execute on each of a plurality of guest virtual machines executing on the host machine and the application whitelist includes application-to-user associations and is stored in memory that is inaccessible to requests of the plurality of guest virtual machines such that the application whitelist is immutable by a guest virtual machine of the plurality of guest virtual machines during a phase in which adherence to the application whitelist is enforced; receiving a request to execute an application on the guest virtual machine, the request being generated at the guest virtual machine responsive to intercepting, by the guest virtual machine, a user-generated request to execute the application on the guest virtual machine, wherein intercepting the user-generated request includes blocking execution of the application, and wherein the request to execute the application comprises an application identifier associated with the application and a user identifier associated with a user requesting execution of the application; comparing the application identifier and the user identifier of the request with the application whitelist; and generating an execution decision, wherein the execution decision indicates whether the application that was requested is allowed to execute on the guest virtual machine.