US Patent 8990944 Systems and methods for automatically detecting backdoors

Techniques for detecting malicious attacks may monitor activities during execution of content (e.g., network downloads and email) to identify an instruction backdoor on a computer. An instruction backdoor is malware that opens a port for listening for instructions from a remote server. Such instructions may trigger activation of malicious activity. These techniques employ virtual machines that, in a controlled and monitored environment, permit content, when loaded and executed, to open ports. When those ports are not the authorized ones used for communications by known programs installed on the computer, an instruction backdoor is discovered.