The results of the survey into public attitudes to internet security were released at the start of the UK's Get Safe Online 2007 road show.
The number of people using security software demonstrates an increased vigilance when it comes to protecting personal computers, but users' actions online put them at increased risk of internet-based crime.
Cabinet Office minister Gillian Merron told the annual Internet Safety Summit in London: "The internet is a fantastic tool, whether you use it at home, at school, at your local library or at work.
"The risks we are highlighting today can be easily fixed and do not mean that people should stop using social networking sites and wireless networks.
"People simply need to take a few basic steps and simple precautions to help keep themselves, their families and their businesses safe online."
Get Safe Online found that over 10.8 million people across the UK are registered with a social networking site, and that one in four have posted information such as phone number, address or email, increasing their vulnerability to identity fraud.
The research also found that 13 per cent of social networkers have posted information or photos of other people online without their consent.
This trend is strongest among younger users, according to the poll. Around 27 per cent of 18 to 24 year-olds have posted information or photos of other people without their consent.
"The popularity of social networking and other sites means that we are much more open about ourselves and our lives online," said Tony Neate, managing director of Get Safe Online.
"Although some of these details may seem harmless, they actually provide rich pickings for criminals. Your date of birth and where you live is enough for someone to set up a credit card in your name, for example.
"So while most people would not give this information to a stranger in real life, they will happily post it online where people they don't know can see it. "
Graham Titterington, a principal analyst at Ovum, commended Get Safe Online on its efforts, but questioned the overall effectiveness of the body.
"It is difficult to separate real security from the perception of security when dealing with the public. Get Safe Online is as much about getting people online as it is about safety," he said.
"It is doing a worthwhile and difficult job in getting the UK online, but its limitations became apparent at the presentation to launch the new campaign.
"It is a user educational organisation, but the problem will never be solved without a holistic approach involving all parties."
Titterington compared Get Safe Online's efforts to similar government campaigns to solve the problems of under-aged smoking and drink-driving.
"It is hard to see how privacy and antivirus will grab their attention in a way that life-saving concerns have failed to do," he said.
"We have to move away from relying on every internet user being a security expert, and put more responsibility onto parties who are in a position to do something about the problem.
"It was also worrying to see that of the seven questions from the floor to the Get Safe Online panel at the end of the presentation only one got a relevant answer.
"This is more a criticism of the industry and of the government's attitude to the internet than a criticism of Get Safe Online itself, but it shows how far we still have to travel."
Surfers unwittingly put themselves at risk
By Staff Writers on Nov 16, 2007 10:11AM
Internet users are at an increased risk of web-based crime, despite 88 per cent having some form of internet security software, according to a poll by Get Safe Online.
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