ScanSafe, a web security firm, has released a report that 68 per cent of malware that it blocked last month came from legitimate sites.

The sites include Walmart’s, Nature.com, Foofighterslive.com, photopass.com, and websiter.edu. In Walmart’s case, some of its pages were compromised by SQL injection attacks. This includes exploiting recent Flash vulnerabilities.

A 220 per cent increase of web-based malware happened over the last twelve months. An 855 per cent increase happened from May 2007 to May 2008 on backdoor and password-stealing malware.

“Currently, thousands of legitimate sites are being compromised daily. The net result is that you absolutely cannot assume that because you are on a brand name or well known site that it is a safe site,” said a senior security researcher at ScanSafe.

Source: Channel Register