1. A method for assigning a vulnerability parameter to a device on a network, comprising: passively determining, responsive to a passively read packet, a vulnerability parameter for an operating system or service; storing, responsive to the vulnerability parameter being passively determined, the vulnerability parameter in a host map associated with a network device; modifying the vulnerability parameter which was passively determined; and storing the modified vulnerability parameter in the host map, wherein the vulnerability parameter is invalid or valid, when the vulnerability is invalid and a pre-defined change in the operating system or service occurs on the network device, a new vulnerability lookup is performed for the changed operating system or service and the vulnerability parameter is remapped from invalid to valid based on the new vulnerability lookup for the changed operating system or service, wherein the vulnerability parameter is associated with a universal unique identifier to distinguish between locally and remotely generated vulnerability parameters and is synchronized to a high availability peer, the vulnerability parameter being propagated from the host map to the high availability peer, when the vulnerability parameter is modified at the high availability peer, the modified vulnerability parameter is propagated from the high availability peer back to the host map.