More than 400 attacks on instant messenger (IM) platforms were spotted last year, an increase of 15 percent from the year before, according to researchers at Akonix.
The total, which marked an annual record, included 41 new attacks in December, according to the San Diego-based firm.
Sohana was the most common IM worm seen during December, with five variants, according to Akonix, followed by Blowhen, which had two variants.
In total, 406 IM attacks were recorded during 2006 - 59 more than 2005.
Public IM traffic is expected to climb from 15.7 billion messages a day in 2006 to 55.7 billion daily messages in 2010, according to a recent Radicati Group study.
Experts consistently warned of a steady increase in IM threats during 2006, citing growing popularity - often unbeknownst to IT professionals - of the communications platform in the workplace.
Don Montgomery, vice president of marketing for Akonix, told SCMagazine.com today that last year's IM threat numbers are near what his company thought they would be.
"We anticipated growth because IM is a clear vector for moving malicious code around. It's pretty much in line with what we predicted," he said. "It's had significant growth, and in addition we did see a number of more sophisticated attacks."
Montgomery added that attacks were spread evenly among AOL, Yahoo, MSN and ICQ messaging platforms.
But researchers have still not figured out why IM attacks have dipped during the summer months for the past two years, said Montgomery.
"The interesting thing was that the growth was about what we expected, but 2006 looked a lot like 2005 in that there was a big dropoff in the middle of the year and then it picked back up at the end of the year," he said. "One theory is that some of the hackers are students, and (the number of threats) picks back up when they get back to school."
Lamar Bailey, senior operations manager at IBM Internet Security Systems X-Force, told SCMagazine.com today that IM attacks will almost certainly increase this year because of the difficulty in blocking messenger threats.
"We are seeing that more people are using instant messenger, and more people are looking to attack. What platform they're using doesn't seem to matter," he said. "Now users have various IM protocols, and a lot of them with Skype are very hard to block completely. So it's not always possible to block all IM traffic."
Paul Wood, senior analyst at MessageLabs, told SCMagazine.com today that the convergence of IM networks will unintentionally lure hackers.
"I would expect them to increase in 2007 almost certainly. One thing that happened in 2006 was for users of MSN and Yahoo to communicate with each other, and later in this year, we expect the same thing to happen with Google Talk and AOL," he said. "So it is really when that ecosystem becomes large enough that IM becomes another vector for a greater number of attacks."
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