1. A method comprising: adapting, by a digital device, a portable document format (PDF) parser, to evaluate a PDF document received over a network; using the PDF parser to examine, by the digital device, one or more portions of the PDF document to determine if one or more suspicious characteristics indicative of malicious network content are included in the one or more examined portions of the PDF document, wherein the one or more examined portions of the PDF document comprise less than an entirety of the PDF document; and when the one or more examined portions of the PDF document are determined to include one or more suspicious characteristics indicative of malicious network content, providing the PDF document to one or more virtual machines associated with the digital device to verify the inclusion of malicious network content in the one or more examined portions of the PDF document by processing at least the one or more examined portions of the PDF document by the one or more virtual machines so as to determine if the PDF document includes malicious network content.