An increasing number of instant messages contain links to malware, say security researchers at Symantec's MessageLabs.
One in 78 links contained in instant messages connect to malware, according to the June MessageLabs Intelligence report.
This represents an increase of nearly 1% compared with six months ago, when only one in 200 links shared by instant messaging were malicious.
Based on these figures, MessageLabs Intelligence predicts that 1 in 80 instant messaging users may expect to receive a malicious message each month.
"The increase in instant messaging - largely a result of Captcha breaking technology allowing bad guys to set up bogus accounts and direct victims to a malicious website - is a challenge that businesses need to get a grip on," said Paul Wood, MessageLabs Intelligence senior analyst.
These kinds of threats are difficult to block, but can be controlled if the relevant personnel take the time to implement an acceptable instant messaging usage policy within the organisation, he said.
According to Wood, carefully monitoring use of instant messaging within a business, in addition to adopting appropriate instant messaging filtering technology, can do a lot to ensure companies don't open themselves up to malicious attacks.