To avoid compromising the security of their system, Microsoft issued a quick fix called Enhanced Mitigation Experience Toolkit (EMET), which the software giant can be downloaded by accessing this link: http://bit.ly/Kv497S.

According to Reuters, the malware was first detected Friday last week by Eric Romang, a researcher from Luxembourg, and identified it as Poison Ivy.

Mr Romang's subsequent analysis showed that Poison Ivy is primarily programmed to breach PCs that were using Microsoft's Internet Explorer by exploiting a bug on the browser, which according to web security specialist Symantec is known as 'zero-day'.

Such vulnerabilities, Symantec said, were deemed in the online security industry as both rare and alarming.

While only eight incidents of zero-day vulnerabilities have been recorded since 2011, "the danger with these types of attacks is that they will mutate and the attackers will find a way to evade the defences we have in place," Symantec's Liam O Murchu told Reuters.

"There are no patches available. It is very difficult for people to protect themselves," Mr O Murchu added.

Microsoft has acknowledged that millions of office and home users are potentially exposed to Poison Ivy's infection, with at least 33 per cent of PCs around the world connected to the net via the Internet Explorer.

When infected, these PCs could be rendered as virtual zombies that cab be controlled by hackers, leaving them at their disposal and serving as platform as well for the malware to further spread on other systems.

To ward off further attacks, Microsoft said it will soon release un upgraded version of its browser but for the time being global user are strongly advised to download and install EMET on their systems, which should keep cyber criminals at bay while the tech giant works on the final solution.

However, the easier fix is to do away with Internet Explorer and use instead Mozilla's Firefox or Google's Chrome since Poison Ivy is not presently known to enter computer systems via other browsers outside of Microsoft's, according to security experts.

Users will skip unnecessary hassles and save loads of time by viewing web pages through Chrome and other alternative browsers out there, McAfee's Dave Marcus told Reuters on Monday.