The software pack, first discovered by Panda Software in May 2007, can be bought online for $1,000 from Russian hackers. The price also includes a year of technical support.

The webpages compromised are all legitimate sites devoted to subjects such as tax, jobs, tourism and cars.

Using the kit, budding hi-tech criminals can churn out code that exploits the latest vulnerabilities in widely used web browsers that work on Windows.

The latest round of infections using MPack is thought to be one of the most successful.

It is believed to have started when malicious hackers got access to one of Italy's largest website hosting companies and seeded servers with the code that attacks anyone visiting those sites.

<url=http://news.bbc.co.uk/2/hi/technology/6221306.stm>BBC News</url>