BANGALORE, INDIA: Security threats are the major concerns in Information Technology. Millions of computers are under the threat of different viruses that can easily give way to criminals, allowing access to personal details.

And it is this threat the world's most popular web browser Internet Explorer is facing today. Microsoft Corporation said that the web browser has some security flaw due to which people using it may have their computers hijacked, says its developer.

70 per cent of computer users access the Microsoft' web browser regularly. Two million computer users have already become victims of the malicious attack, say reports.

Owing to the flaw in the browser, 'Trojan horse' viruses can be injected into the software of millions of computers, allowing criminals to remotely access and operate them.

So far hackers have only tried to steal the game passwords that can be sold in the black market. But there are fears of hackers getting into Internet bank accounts and steal the passwords or send out spam mails.

Admitting that there is a security flaw, Microsoft said only the Internet Explorer 7 has been affected and efforts on to update the security at the earliest.

"Microsoft teams worldwide have been working round the clock to develop a security update to help protect our customers and released our Advanced Notification Service advising customers that we will be releasing that Security Update at roughly 10 am PST (around 11 pm IST) on December 17, to protect them from the vulnerability," said a Microsoft spokesperson.

"The Microsoft Security Response Center continues to monitor the threat landscape while working, and sharing information with, partners around the globe through the Microsoft Active Protections Program to help protect our mutual customers."

Until the update is available, Microsoft advised the customers to follow the 'Protect Your Computer Guidance' at www.microsoft.com/protect, which includes activating the Automatic Update setting in Windows to ensure that they receive the update as soon as it is available, enabling the firewall, ensuring antivirus and antispyware is up to date.

Customers can also take additional precautions by setting their Internet Explorer security settings to "High" and using Internet Explorer 7 in "Protected Mode."

Gmail had recently said that Internet Explorer 7 can be used for a faster browsing experience, thus prompting many users to download the new version.