An analysis of 100,000+ Windows malware samples has revealed the most prevalent techniques used by malware developers to successfully evade defenses, escalate privileges, execute the malware, and assure its persistence. Malware tactics and techniques The analyzed malware samples were most often delivered via malicious email attachments featuring macro-enabled documents, Windows shortcut files (LNK), ISO/VHD containers, and MSI installers.

Source: Help Net Security