Welcome to the August edition of the Symantec Intelligence report. Symantec Intelligence aims to provide the latest analysis of cyber security threats, trends, and insights concerning malware, spam, and other potentially harmful business risks.
As reported in the ISTR Volume 19, 2013 saw a 500 percent increase in ransomware in the latter part of the year. Overall ransomware levels remained high through March 2014, and then slowly started to decline, in part due to the disruption of the GameOver Zeus botnet back in late May.
In contrast, crypto-style ransomware has seen a 700 percent-plus increase. These file-encrypting versions of ransomware began the year comprising 1.2 percent of all ransomware detections, but now make up 31 percent at the end of August. One variant known as Trojan.Cryptodefense began to appear in large numbers in early June. By the end of July, it made up 77 percent of all crypto-style ransomware for the year to date. This follows predictions in the ISTR saying this type of malware would become more common in 2014.
Over 31.5 million identities were reported exposed in August, from 12 incidents. The jump in exposed identities is due to a large breach in South Korea, comprising 27 million identities. In the last 12 months 53 percent of data breaches were caused by hacking and 21 percent were accidentally made public.
The average number of spear-phishing emails blocked each day for August was 20, compared with 54 in July and 88 in June. This is below the year-to-date average of 86, which is slightly higher than the daily average of 84 for all if 2013.
The most frequently used malicious file types in these email-based targeted attacks were .exe and .doc file types, with .exe attachments coming out on top this month at 31.8 percent. 29 percent of spear phishing emails were sent to Manufacturing, returning it to the top of the industries targeted.
One in 1,587 emails was identified as a phishing attempt, compared with one in 1,298 for July and one in 496 in June. While at first glance this looks like a big drop, it is not indicative of a wider trend just yet, resulting in only a 0.01 percentage point decrease in the overall phishing rate.
We hope you enjoy the July Symantec Intelligence Report. You can download your copy here.