5. Malware Infection
Malware was tied to 40 percent of all breaches, Verizon found. Direct installation of malware by an attacker already on a system is the most common attack vector, accounting for 74 percent of all breaches, Verizon said. Malware distributed via email accounted for 47 percent of all breaches, according to the analysis. A malicious email attachment was used in many espionage breaches. Drive-by downloads accounted for only 8 percent of breaches.