Spam levels declined 24 percent from the third quarter to the fourth. But levels picked up again as scammers looked to cash in on last-minute shoppers.
The report shows the U.S. still leading in spam production, followed by Brazil and India. Other findings include the fact that more and more threats were Internet-based and portable storage device threats hit an all-time high, as has rogue security software.
Earlier this month, Sophos noted a rise of 70.6 percent in social-networking spam and a 69.8 percent rise in malware being sent.