Attacks on instant messaging (IM) have risen markedly in the last year, and the software category looks set to be the threat story of 2006, IMlogic has claimed.

Year-on-year rises of over 800 percent to were recorded by the company’s Threat Center up to December 2005. The final quarter of the year, in particular, saw record levels of malware targeting IM.

The number of threats targeting the different platforms, broadly reflected their popularity, with Microsoft’s MSN service accounting for 48 percent of the threats recorded in December. AOL accounted for a further 41 percent, with Yahoo on 11 percent.

Other IM systems such as ICQ registered small numbers of attacks in previous months, and it is clear that the particular system that scores the highest in a particular month can change from month to month.

Notable IM worms included the “Santa” worm, which was unusual in being aimed at all IM networks, and the “talking” IM.Myspace04.AIM worm, capable of interacting with users in a rudimentary way to aid its spread.

Overall, worms made up 87 percent of new IM malware, with viruses a distant second at 12 percent. Phishing barely registered at one percent.

"The growth in the level of sophistication and the advanced nature of the malware payloads such as root kits and information gathering agents sends a signal to IM users that IM security is no longer a 'nice to have' technology," said company CTO Jon Sakoda.

"This rise in complexity and destructive nature of the threats requires organizations and individuals to put in place more adequate protections."

Separetely, IMlogic has announced that it is to be acquired by the voracious Symantec, a move that signals that IM security is now considered a mainstream – and potentially profitable - concern.