"At this time, Microsoft is aware only of limited, targeted attacks that attempt to use this vulnerability," wrote Bill Sisk, Microsoft's security response communications manager, in an e-mail statement.
The vulnerability in question is a classic remote code execution (RCE) attack class through a client-side vector. In order for a hacker to exploit this vulnerability, a user would have to open a maliciously configured Word document, allowing the attacker to gain entrance into the processing environment and perhaps the whole network to gain superuser access.
This is a common method among hackers leveraging RCE exploits since Microsoft Office documents are used quite frequently in enterprise environments all over the world.
Meanwhile, as far as this particular advisory is concerned, Sisk offered no indication or assurance that the issue would be patched anytime soon. He explained that advisory "may not require a security bulletin but could still affect a customer's overall security."
Users of other Microsoft Word versions and service packs will not be affected, according to Microsoft's investigation. Redmond ruled out other Office components too. "Microsoft Office Word, Microsoft Office Word Viewer, Microsoft Office Compatibility Pack for Word, Excel, and PowerPoint 2007 File Formats, and Microsoft Office for Mac" all are not affected by this vulnerability.
This latest advisory, announced late Tuesday, marks the fourth off-cycle security threat advisory since June 30. Some security experts have said that Microsoft's rating system for patches and threats may be understated, and such off-cycle announcements give credence to that notion.
In the meantime, prior to Microsoft issuing a patch, Redmond recommends using the Word Viewer program that is designed to protect against such exploits upon opening a file.
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