Purportedly, Microsoft has already started its investigations concerning a possibly severe and dangerous DOS-attack-based (Denial of Service) security hole affecting its present flagship program, Windows 7. The operating system vulnerability that's present in both Windows 2008 R2 and Windows 7 makes it possible to freeze up susceptible machines. There are no Blue Screens of Death, error messages, or any other visible alarm indicating that anything was out of place; it's just causes a straight-out, out-of-the-blue lockup or computer hanging.

The vulnerability brings about a system freeze that can be activated from a remote location by sending distorted packets to the intended systems, particularly the Network Basic Input/Output System (NetBIOS) header that identifies an inward bound Server Message Block (SMB) packet that's four bytes larger or smaller than it really is. On a side note, SMB is a network protocol that's utilized in order to gain shared use of printers and files.

Laurent Gaffié, a white hat security expert, posted a proof of concept for the bug on his blog this Wednesday. In it, he alleges that a user can be remotely terrorized by this freeze vulnerability via broadcasting nbns tricks or browsing Internet Explorer regardless of how high your firewall's restraints are set to. Gaffié was the same researcher who exposed the flaws in Microsoft's SMB implementation that caused an even larger code execution risk just last September.

Needless to say, the remote kernel crasher code is a very crippling security hole that must be investigated and patched as soon as possible. However, even though the vulnerability is capable of knocking over different computer networks, there's still no proof that this flaw is exploitable via code infection, which is a far more perilous type of hacking quandary. All the same, news of the code flaw appeared a day after Microsoft's hefty Patch Tuesday updates arrived, so of course it's still a concern for many a Windows 7 user.

The latest Patch Tuesday updates included the MS09-065 fix for a critical vulnerability in the Windows kernel of Windows Server 2003, Windows XP, and Windows 2000. What's more, the same patch also contained a lesser risk fix for Windows Server 2008 and Windows Vista. In any case, this particular patch and the two other Windows-based fixes released earlier this week have nothing to do with Windows 7's security problems whatsoever.