The FTC has written to the organisations, which range from school authorities and local government departments through to large scale enterprises, after it was discovered that sensitive information was being distributed over P2P networks.

P2P networks are widely used to transfer files between computers but, because of their automatic nature, users are often unaware as to when another P2P user is downloading a file from their PC. It is believed that the breach has arisen due to computers which were not correctly configured, potentially due to a lack of a firewall or other traffic monitoring software.

“Unfortunately, companies and institutions of all sizes are vulnerable to serious P2P-related breaches, placing consumers’ sensitive information at risk,” said Jon Leibowitz, chairman of the FTC.

“Companies should take a hard look at their systems to ensure that there are no unauthorized P2P file-sharing programs and that authorized programs are properly configured and secure.”

As well as notifying companies of the breach, the FTC is also planning to launch a new education campaign aimed at helping companies secure systems for P2P connections but have reiterated that IT security, as well as compliance with data privacy laws remains the responsibility of the companies involved.

“It is your responsibility to protect such information from unauthorized access, including taking steps to control the use of P2P software on your own networks and those of your service providers,” the commission warned.

The term ‘drive-by download’ has a number of definitions but is, in principle, the process where malicious software is downloaded to your PC without your consent or knowledge. This is most commonly due to visiting an infected website, opening a seemingly legitimate email attachment or installing an unknown browser Plugin.

Regardless of how you come across a drive-by download, they almost exclusively work by exploiting a vulnerability in your browser. For that reason, it is essential to ensure that you regularly update your browser as well as your antivirus software. Other browsers, such as Google Chrome or Mozilla Firefox, sell themselves on the claim that they are less susceptible to such attacks than Microsoft’s Internet Explorer.

But this form of attack has come a long way since the days of the pop-up ad explaining how to claim your free laptop or inviting you to play a duck shooting game and it is something of a fallacy that the only sites where malware resides are suspicious looking URL’s from notorious virus hot spots -far from it. In recent years, malware distributors are increasingly looking to exploit weaknesses in web and ad servers in many of the world’s respected websites. In September 2009, ads on the New York Times website were infected with malicious software whilst the website of the Daily Mail has also been the target of a similar attack.

The advice to computer users is simply to make sure that your antivirus software is installed and up to date and that they also install the latest security updates and bulletins for your browser software. Also consider using a firewall, a system that prevents unauthorised traffic from entering and leaving your PC, which can be found in most antivirus software packages.

Chinese computer experts highlighted a flaw in a the screening software which could lead to a “large-scale disaster” just a day after the software was made compulsory for all computer systems sold within the country.

The Chinese government, which employs strict censorship laws on the media and electronic communications, mandated that all computers in the country must include a form of screening software which is designed to filter out any offensive content from the internet.

But researchers have revealed that the software contains a series of flaws that could allow a hacker to distribute malicious software including computer viruses and spyware.

“We found a series of software flaws,” Isaac Mao, a blogger and social entrepreneur in China, as well as a research fellow at Harvard University’s Berkman Center for Internet and Society, told the BBC.

In one example, Mr Mao highlighted that tests had shown that communications between the software and the servers at the company that developed the program were unencrypted.

He claimed that this could allow hackers to “steal people’s private information” or “place malicious script” on computers in the network to “affect [a] large scale disaster.”

The launch of the software has attracted further criticism, with claims that the filter is only effective on Microsoft Windows PCs and running the Internet Explorer browser. Those using Mac or Linux operating systems, as well as Windows users opting for alternative browsers such as Firefox have reportedly been able to bypass the software.

China has long had a policy of restricting internet use in the country, with several high profile sites and news agencies banned to Chinese users in what has been dubbed “The Great Firewall of China” in what is widely seen as an attempt by Chinese authorities to play down criticism of the country’s current regime.

In response to criticism from the Western media, Chinese authorities relaxed many restrictions during the 2008 Beijing Olympics but more recently, sites such as Blogger and Twitter were reportedly banned to Chinese users last week due to the 20^th anniversary of the Tiananmen Square protests.