France has echoed calls by the German government for web users to find an alternative to Microsoft’s Internet Explorer (IE) to protect security.

Certa, a government agency that oversees cyber threats, warned against using all versions of the web browser.

Germany warned users on Friday after malicious code – implicated in attacks on Google – was published online.

But Microsoft told BBC News that IE8 was the “most secure browser on the market” and people should upgrade.

Cliff Evans, head of security and privacy, said that so far the firm had only seen malicious code that targeted the older version of its browser, IE6.

“The risk is minimal,” he said.

For a web user to be affected, he said, they would have to be using IE6 and visit a compromised website.

“There are very few of them out there,” he told BBC News.

However, if this did occur, a PC could become infected with a “trojan horse”, allowing a hacker to take control of the computer and potentially steal sensitive information.

‘Sophisticated attack’

Although the vulnerability has so far been exploited only in IE6, security researchers warned that could soon change.

“Microsoft themselves admit there is a vulnerability, even in IE8,” said Graham Cluley of security firm Sophos.

Mr Cluley said that because details of the exploit were now available online, hackers could soon change the code to target other versions of the browser.

He warned web users to be careful about clicking on links in unsolicited e-mails and advised all web users to upgrade their browser to the latest version, no matter which software they used.

The advice follows revelations that a “targeted and sophisticated” attack on Google exploited the vulnerability.

Google said last week that an attack on its corporate network had targeted the e-mail accounts of human rights activists.

The attack led Google to announce that it might withdraw from China, after it revealed that the attacks had probably originated in the country.

Following the news, Germany’s Federal Office for Information Security issued a warning against all versions of Internet Explorer and recommended that users switch to an alternative such as Firefox or Google’s Chrome.

The French agency Certa issued a similar warning.

“Pending a patch from the publisher, Certa recommends using an alternative browser,” it said.

The UK government had said that it would not issue a similar warning. However, it said the Centre for the Protection of National Infrastructure (CPNI)was “monitoring the situation” and would “publish further advice if the risks change”.

By Jonathan Fildes
Technology reporter, BBC News

Microsoft response: “cannot recommend people switch due to this one flaw”. Well exactly how many flaws does it take? How serious do those flaws need to be?