Technology security firm Sophos says China ranks first in its list of countries that host malware threats.

Sophos says its data shows a sharp rise in web-based threats. Sophos uncovered an average of 29,700 new infected web pages every day, around 80 percent of which were located on hacked legitimate sites.

As of June 2007 the top ten countries hosting malware-infected websites are:
1. China (including Hong Kong) at 59.3%;
2. United States at 23.9%;
3. Russia at 3.6%;
4. Germany at 1.7%;
5. Ukraine at 1.4%;
6. Italy at 1.0%;
7. Taiwan at 0.8%;
8. Brazil at 0.8%;
9. United at Kingdom 0.8%;
10. Canada at 0.6%.

"The number of new infected web pages identified each day in June more than tripled compared to May, a clear indicator that malware being hosted on exploited websites due to vulnerabilities is steadily climbing," said Ron O'Brien, senior security analyst at Sophos. "Organizations and owners of websites need to reassess their security to ensure that visitors are not being infected."

Iframes, which work by injecting malicious code onto web pages, has again topped the chart, accounting for nearly two thirds of the world's infected web pages. Earlier this month, an Iframe attack on multiple Italian websites occurred, making headlines around the world. More than 10,000 web pages were infected, most of which were on legitimate but compromised websites hosted in Italy. Victim websites included Italian city councils, employment services and tourism sites. Most of the affected pages appear to be hosted by one of the largest ISPs in Italy.