Hackers have crafted several exploits for security vulnerabilities that Microsoft patched last Tuesday.
The availability of exploits promoted McAfee to raise its Global Threat Condition to 'severe', the third highest rating on a four-step scale.
Proof-of-concept code has emerged that exploits a flaw in the way that Windows handles images in the ART format.
Exploits have surfaced that target flaws in Windows Media Player and Word as well as the Windows Routing and Remote Access Service, the Server Message Block feature and a flaw in Windows' TCP/IP Protocol driver, according to the SANS Internet Strom Centre.
The latter two are rated 'important', and Microsoft has issued a severity rating of 'critical' for the other three vulnerabilities.
Attackers had been exploiting the Microsoft Word vulnerability prior to the patch release to stage highly targeted attacks.
A disgruntled programmer published proof-of-concept code for the Routing and Remote Access Service vulnerability after Microsoft failed to acknowledge him in a security advisory.
The software vendor has since edited the bulletin to correctly reflect the programmer's contribution.
Although iDefense has had ample time to create the proof-of-concept code, it demonstrates that malicious attackers would be able to craft a similar exploit.
Hackers in recent months have increased the speed at which they create exploits for recently patched security flaws. This allows them to target systems whose users have not yet installed the latest updates.
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