The torrent in spam that started in October may slow slightly after the first of the year, but users should expect more junk mail than ever in 2007, a messaging security company predicted Thursday.
Spam volume is up 73% in the last three months, Postini reported, thanks to a one-two-three punch of a huge increase in the number of spam botnets and a major jump in the use of both image- and document-based spam. For the year, spam quantity is up 143%.
"It's a triple threat, a perfect storm," says Dan Druker, a Postini executive VP. "Spammers are using much more difficult [to stop] techniques than in the past, and the botnets are much bigger." Some days in November, Postini, which offers enterprises managed antispam services, counted a million different IP addresses bound to incoming junk mail.
"The character of what they're sending has also changed," charges Druker. Like other spam experts, Druker notes a big bump in image-based spam, junk mail that abstains from using text, which antispam software analyzes, and instead plants the message in an image. Sniffing through huge quantities of image spam, says Druker, is almost impossible for local antispam defenses, whether appliance- or software-based.
According to Postini's data, image- and document-based spam—the latter is when a junk mailer tucks the marketing message inside a document attached to a message—accounted for as much as 45% of all spam in the fourth quarter, up from less than 2% a year ago.
"The combination of the [high] volume and the type of spam now coming in is what's causing companies' defenses to melt down," Druker says. "They just can't keep up with the rising tide."
Although an increase in spam is normal during the fourth quarter, the current crush of junk mail is definitely out of the ordinary. That means come 2007, users will be living with more spam than ever. "[The volume] will drop off a little bit, but the [spam] graphs will be taller and broader than ever before next year," says Druker.
While the war against spam may not be lost, as other experts have claimed, Druker paints an ugly picture for 2007. "The more high-speed connections and the more Windows PCs there are gives spammers that much more raw material," he says. "Until home PCs get locked down, I don't see attacks going down. Only when [consumers] start locking down their computers will we see a big difference."
Millions of PCs, the majority of them machines in non-business settings, have been hijacked and forced to send spam by a new wave of malware, including the prolific Stration (aka Warezov) line, which first made an impression on security vendors in October. "Worm attacks are now predictive of massive spam attacks," Druker says. "Massive botnets give spammers an unlimited free capacity to send billions of messages."
In particular, the large increase in botnet use by spammers has made some antispam tactics, such as blacklisting specific IP addresses, ineffective.
Druker's dim prognosis is at odds with forecasts made as recently as earlier this year, and as far back as January 2004, when Microsoft chairman Bill Gates swore that spam would be licked within two years.
"Everyone thought this was a solved problem," says Druker. "But now it's the worst it's ever been."