Websites with the most robust reputations are prime targets for hackers, according to internet security experts.


A report from Websense shows that during the first six months of 2008, three-quarters of legitimate websites were compromised, which represents an increase of almost 50 per cent on the previous six months.


Carl Leonard, the threat research manager for EMEA at Websense, said that companies should be able to scan, analyse and classify content at all times – and in real time.


Also, Websense revealed that email spammers have broken the CAPTCHA response testing safeguards that use a challenge-response test that is meant to distinguish between input generated by humans and computers. Its aim is to prevent fraudsters from registering accounts automatically by using trusted names such as Gmail and Windows Live Mail. The email addresses that are generated are then used by hackers to bypass filters that don't reject these messages.


Leonard called for CAPTCHA systems to be improved and recommended that businesses should consider employing a data-centric approach to security.


“Security needs to be geared up to look at contents of web pages and all the data surrounding the sending of emails such as the reputation of the sender, the URLs involved in the emails, and the pattern of attacks,” he added.