'DonBot' makes an offer Twitter can't refuse.

A major malware botnet has sprung to life and is making a massive spam run through social networking sites.

Researchers with Symantec's MessageLabs branch said that the DonBot network has recently begun sending out spam emails in large numbers, accounting for as much as 4 percent of the total global spam load since Wednesday 18 November.

The messages advertise a 'work at home' programme which promises users as much as US$300 per day posting information online.

"The apparent aim of these e-mails is to get people to fall for 'get rich by working at home' schemes where the victim is encouraged to pay an initial fee for a trial and then sit back and watch the cash come in," wrote Symantec malware analyst Mat Nisbet in a blog posting.

Upon clicking on the spam image, users are redirected to one of any number of Twitter pages which contain links to a third-party site which asks the user to pay the 'trial fee' for the programme.

Researchers believe that the operation utilises both hijacked and specially created spam accounts on Twitter. Some hijacked Facebook pages are also being used to spread the links.

Social networking sites have become a favourite tool for scammers and malware writers as of late. Attackers have used sites such as Facebook and Twitter to not only spread spam but also to infect new users.