Update: Microsoft has patched the issue and it is no longer a problem provided that Windows users have patched their system with the most recent security updates provided by the company.
An unpatched bug in the Windows XP Help and Support system is being increasingly used in attacks by virus and malware writers reports the BBC.
Microsoft reported it's seen more than 10,000 PCs hit by the attack so far and that it has not been able to find a fix for the problem.
A successful exploit of the issue gives hackers complete control over the PC. It initially came to light when a Google Engineer discovered it was possible to exploit Windows XP's ability to send and receive remote help from another computer.
Microsoft said it only saw "innocuous" attacks by a few researchers first but discovered later on that hi-tech criminals are exploiting it as well.
Writing on the Microsoft Security Centre blog, Holly Stewart said it had started seeing "seemingly-automated, randomly-generated" web pages that host the exploit.
A senior security researcher at Trend Micro, Rik Ferguson, said "It's certainly very serious and is now being actively exploited by what appears to be several different groups as you can see form the multiple payloads being delivered." and Carole Thierault, senior security consultant as security firm Sophos described the attacks as a "nightmare".
Microsoft is still working on a fix for the problem but Engadget have reported that...
Microsoft says the only current work around to the issue is to Unregister the HCP Protocol which disables hcp:// style links
The vulnerability does not affect Windows Vista or Windows 7. Users should avoid clicking on links that begin with hcp as that is the requirement for an successful attack on the user system.
Windows XP and Windows Server 2003 users can read the following guide to find out how to protect their system from the attack: Windows XP And Windows Server 2003 Zero-Day VulnerabilityAdvertisement
Ghacks is a technology news blog that was founded in 2005 by Martin Brinkmann. It has since then become one of the most popular tech news sites on the Internet with five authors and regular contributions from freelance writers.