Cape Town - A zero-day vulnerability has been discovered in Microsoft's Internet Explorer that could give hackers access to a computer.
"Researchers have observed attacks using this remote code execution vulnerability to install malware that attempts to disable the user's security products and redirects banking sites to a malicious IP address," security firm Trustwave said.
A zero-day vulnerability is one that is known, but software patches have not yet been built to close the software flaw.
Trustwave discovered that hackers are exploiting the vulnerability in Internet Explorer 8 "in the wild" by using it to install malware on infected machines.
The distribution model is closely linked to visiting compromised websites and the target has mainly been users of online banking platforms, Trustwave said.
So far, it appears that the attacks have been limited to computers that are set to run in Korean and Japanese.
"This Internet Explorer zero-day is currently used only on a small number of websites, and the attack was limited by its programmer to Japanese and Korean users. However, based on past experience, new drive-by exploits are quickly copied to other malicious sites because they can work against large number of users," said Trustwave director of Security Research Ziv Mador.
The company added that the vulnerability extends to Windows XP and 7 platforms, and that the flaw was reported to Microsoft.
It is recommended that users download the latest Microsoft patch issued on Tuesday by enabling Windows Updates.
Internet Explorer's share of users declined to 12.1% from 16.4% from a year ago, far behind market leader Chrome which commands of 53.2% of the browser market, according to w3schools.com.
Mador indicated that user banking information was the target of the attacks.
"The malware in the specific attack we observed is responsible for a number of malicious activities: It attempts to disable any security products that may be running on the victim's computer, redirects banking sites to a malicious IP address, and tries to steal credentials to popular online games."
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