Analysis reveals that targeted attacks have increased significantly since they were first discovered five years ago from one to two attacks per week in 2005 to 77 attacks per day in October 2010, according to Symantec.
For the first time, targeted attacks hit the retail sector hardest this month where they increased from a steady monthly average of .5 percent of all attacks over the past two years to 25 percent in October characterized by a retail organization that was the intended recipient of three waves of highly targeted spear phishing attacks. In October, 1 in 1.26 million emails comprised a targeted attack.
Typically, between 200 and 300 organizations are targeted each month with the industry sector varying. Over time, the same individuals are targeted but using different exploit methods. For example, in October, an average of 5.4 users was targeted within each organization.
“While targeted emails by nature are sent in low volumes, they are one of the most damaging types of malicious attacks,” said MessageLabs Intelligence Senior Analyst Paul Wood. “We have seen a constant influx of targeted attacks over the past six months with the type of organization targeted changing on a monthly basis and the number of targeted users increasing each month. Although the number of unique attack exploits being deployed has diminished slightly, the number of attacks used by each exploit has increased.”
In October, the number of targeted attacks aimed at businesses in the retail sector rose considerably above the monthly average of 1 in 1.26 million, increasing the likelihood of an attack by a factor of almost 6.3 times. Moreover, the number of attacks against the retail sector jumped to 516 in the last month, compared to just seven attacks per month for much of 2010 marking the first time the retail sector had been the focus of a targeted attack campaign in recent years.
“Of the 516 attacks, only six organizations were the intended targets but two of them were mainly targeted one of which was the target of 63 percent of the 516 attacks,” Wood said. “The spear phishing attacks, launched in three waves each one week apart, used social engineering techniques to distribute legitimate-looking emails from HR and IT staff of the targeted organization but in actuality contained malicious attachments.”
Each wave was comprised of one or two different e-mail messages using different themes. The first wave of e-mails targeted 50 recipients and spoofed an email address from the firm’s Senior HR Executive with subjects referring to confidential salary information. The attachment contained a malicious PDF. The second wave also spoofed an HR Executive and targeted 20 recipients with a subject line pertaining to new employment opportunities.
The malicious attachment was an XLS file. The third wave took a slightly different approach and spoofed one of the organization’s Senior IT Security Executives. It targeted 70 employees and requested action with a critical security update. The malicious attachment was a password-protected zip file.
“Examination of the attacks’ timing and techniques suggests a methodical approach on behalf of the attackers,” Wood said. “In the case that the recipient clicked on any of the three malicious attachments, a backdoor Trojan would have been installed onto the computer with the potential for the attacker to gain access to any sensitive personal information or valuable corporate data on the machine.”