Today, the French government followed suit, issuing an advisory suggesting that all versions of Internet Explorer, which is included with Windows, are vulnerable to the attack that was used against Google, Adobe and an estimated 30 other western companies, by hackers originating in China.

Google said the attacks were used to steal intellectual property and compromise email accounts, and identified Internet Explorer as the weak point that was exploited.

The specific version of the browser known to be vulnerable to the attack mounted on Google is Internet Explorer 6 (IE6), which was first released in 2000 and is standard on Windows XP, which was released in 2001. Despite its age and known weakness to hacking, IE6 is still the most widely used browser in the world, ahead of newer, more secure versions and rivals' alternatives such as the free Firefox, Opera or Safari browsers.

IE6 is extensively used by the British government, including UK armed forces: in response to parliamentary questions asked last year by Labour MP and former Cabinet Office minister Tom Watson, the Ministry of Defence, which has 300,000 desktops worldwide (including ships), said it was sticking with IE6, “and at the current time does not have a requirement to move to an updated version”.

via UK ignores fears over Internet Explorer despite French and German warnings | Technology | guardian.co.uk.