IM Attacks On the Rise

As instant messaging becomes an increasingly business critical tool, it's also getting targeted for more hacker attacks at a rather alarming rate.

That's the word according to messaging security vendor Postini, which on Monday released its Message Security & Management Update for July. The report identified a 160 percent increase over June in IM attacks against corporate networks.

Among the more disconcerting attacks Postini detected was Prokeylogger, which logs keystrokes, captures passwords and screenshots, and forwards them to identity thieves.

On a positive note, Postini also reported a rise in the use of encrypted e-mail messages, which demonstrates that organizations are becoming more aware of the problem.

Postini, itself, processed more than 325 million encrypted messages in July, which is a 13 percent increase over June but still represents only 8 percent of all valid e-mail messages.Postini's researchers point out that all modern e-mail servers now have built in Transport Layer Security (TLS), which encrypts e-mail. Postini's research shows that even though the use of TLS is increasing each month, almost 90 percent of businesses worldwide simply don't use it. Postini processed more than 26 billion SMTP e-mail connections in July, with 62 percent blocked as Directory Harvest Attacks (DHAs) and other messages sent to nonexistent recipients. The company blocked 6 billion messages it identified as spam--an average 77 percent of all e-mail scanned--and also blocked more than 26 million viruses in July.

NEXT: Top five viruses for July.

The top five viruses for July were: