Criminal gangs have been busy cold calling UK web users trying to sell them fake anti-virus software, a campaign group has warned.
One in four British adults have been contacted by people purporting to be from legitimate IT companies and promising to fix computers for a price, Get Safe Online has warned.
A typical fee is around 30, but the cyber criminals are after more than a one-time payment they also want credit card details or remote control of the victim's computer.
To do this they will tempt the user into downloading fake anti-virus software, which will then infect the victim's system and steal their data.
Recent cases have seen between 300-400 people working on such an operation, using "call centre scale set ups," explained Sharon Lemon, deputy director for cyber crime at the Serious and Organised Crime Agency (SOCA).
"They can also be paying out as much as $150,000 (93,300) a month (on a pay per download basis) to individual webmasters who are unwittingly advertising their fake software this level of investment from criminals indicates that the returns are much heftier than this," Lemon added.
"Given that our latest research indicates 80 per cent of UK internet users have never heard of these IT helpdesk' scams, yet almost a quarter have been approached by them, it is vital that we make people aware of this threat," said Baroness Neville-Jones, minister of state for security.
Get Safe Online research also discovered 48 per cent of UK web users had seen a pop-up window appear on their screen warning them their computer was infected.
While gangs use the internet as a launchpad for their attacks, the use of telephones has signalled a shift in their tactics.
"The one-to-one nature of the telephone calls also signals a more invasive approach," said Dr Emily Finch, criminologist at the University of Surrey.
"Telephone calls use the personal touch to gain trust. By knowing just a little bit of information about someone (e.g. date of birth, full name, address easily obtainable by fraudsters who know where to go), criminals begin to sound credible and plausible in their approach."
The research comes at the start of the Get Safe Online awareness week designed to help people use the internet safely and protect their PCs.
Fake anti-virus has been a growing problem of late. Earlier this year, Google research showed fake anti-virus accounts for 15 per cent of all malware on the web.
