In December, the company's lab collected more than 214,000 samples of Android malware, compared to approximately 41,000 in September. In July, the number was still as low as 14,000 samples. Additionally, Commtouch researchers also observed a significant increase in email-borne malware during the fourth quarter of 2012.
India remained the number one hotspot for spam-sending zombies in the fourth quarter. With a share of 17.5 percent, India fell below the 20 percent mark but remained ahead of China (9.5 percent) and Vietnam (8.0 percent). Asia remained the dominating region in this list with Pakistan (fifth place), Iran (sixth) and Kazakhstan (tenth) also being among the top ten. The United States came in eighth place with a share of 2.7 percent.
In Web security, education-related sites topped the list of sites most frequently compromised with malware or hiding phishing and spam sites. For example, during the fourth quarter, Harvard University's Department of Government Web site was hacked and used to host a pharmacy page. Other Web site categories particularly vulnerable to being manipulated were travel, sports, business and entertainment sites.
Spam levels remained fairly constant with the expected drop around the Christmas and New Year period. The average daily spam level was 90 billion messages per day - a slight increase over the third quarter of 2012. The lowest level was 52 billion recorded on the last day of 2012 and the highest was an unusual spike of 134 billion at the start of December. Spam averaged between 71 and 80 percent of all emails sent globally during the fourth quarter of 2012.
"Android is by far the most popular mobile operating system in the world today, with a market share of more than 75 percent in the third quarter, according to industry analysts," said Avi Turiel , director of threat research and market analysis at Commtouch. "Its popularity makes it a natural target for cybercriminals of all kinds. The alarming growth rate also demonstrates that the Android platform is still regarded as an easy target."
For more details, you can download the report here. The quarterly report is compiled based on an analysis of billions of daily transactions handled by Commtouch's GlobalView Cloud.
By subscribing to our early morning news update, you will receive a daily digest of the latest security news published on Help Net Security.
With over 500 issues so far, reading our newsletter every Monday morning will keep you up-to-date with security risks out there.