Spyware accounts for 90 per cent of malware

Around 90 per cent of malware found on both home and corporate PCs is spyware, according to internet security firm Panda Software.

Panda said it arrived at the figure after analysing data gathered from an online scanning utility. CTO Patrick Hinojosa said similar studies had found that around 90 per cent of computers are infested with spyware.

"Spyware is installed by many different methods and the infection is not usually visible to the user. These factors increase the infection rate for this type of malware," said Hinojosa.

Panda's findings do not surprise James Turner, security analyst at Frost & Sullivan, who said one of the difficulties when calculating spyware infestation was defining what was spyware and what was not.

"One of the things that fall into this category are cookies. You can say cookies from one particular site are spyware while cookies from another - such as Hotmail for instance - are not. There have been cases where an anti-spyware company has been taken to court by another company claiming its software is legitimate," said Turner.

He added that until anti-spyware utilities are easier to use, the majority of internet users will not be able to adequately protect themselves.

"It is hard for people to draw a line in the sand and say these cookies are okay and those are not okay. At that point it gets quite technical because the tools have not made it simple enough yet. It is still a new and emerging area," said Turner.

Munir Kotadia writes for ZDNet Australia