Spammers are using spyware to launch more sophisticated and targeted attacks, according to email security specialist MessageLabs.
The company claims to have discovered the new technique from analysis of the 50 million emails it scans every day.
Paul Wood, MessageLab's chief information analyst, told vnunet.com: "We began seeing patterns in the emails that seemed specifically targeted at some individuals using familiar names or even passwords and pets' names.
"We suspected something like this might happen, but not just yet. The spammers are always shifting the battle lines and this could be a trial to see how it goes."
MessageLabs said that the perpetrators appear to be using spyware to gather information from PCs which is then used in the subject line of subsequent junk emails to try and persuade targets to open the emails.
"There is no indication of how they are getting the information at the moment. But I would not underestimate the spammers' abilities," said Wood.
"They are well-funded and hooking up with virus writers. Whether they are finding vulnerabilities in current spyware they are exploiting, or developing it themselves, is difficult to say at the moment."
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