Microsoft has confirmed reports of vulnerability in Word that allows an attacker to exploit a system via the Microsoft Jet Database Engine, which shares data with Access, Visual Basic and third party applications.
Microsoft in its advisory said the potential for attack is "very limited." Reports of the Word flaw were highlighted by Panda and Symantec in the last two weeks. On March 3, Panda researcher Ismael Briones stumbled on the new exploit. On Thursday, Symantec also noted the Jet vulnerability. According to Symantec.
The attacker needs only to find a trick to force the MS Jet library to open the file and trigger the vulnerability that will run the malicious shellcode. Some social engineering and a little help from Office applications will work out well in this specific attack. In fact, it is possible to call MSJET40.DLL directly from MS Word, without using Access at all.
Microsoft said in its advisory:
Customers running Windows Server 2003 Service Pack 2, Windows Vista, and Windows Vista Service Pack 1 are not vulnerable to the buffer overrun being attacked, as they include a version of the Microsoft Jet Database Engine that is not vulnerable to this issue.
Customers using Microsoft Word 2000 Service Pack 3, Microsoft Word 2002 Service Pack 3, Microsoft Word 2003 Service Pack 2, Microsoft Word 2003 Service Pack 3, Microsoft Word 2007, and Microsoft Word 2007 Service Pack 1 on Microsoft Windows 2000, Windows XP, or Windows Server 2003 Service Pack 1 are vulnerable to these attacks.
Microsoft is investigating the public reports and customer impact. We are also investigating whether the vulnerability can be exploited through additional applications. Upon completion of this investigation, Microsoft will take the appropriate action to help protect our customers. This may include providing a security update through our monthly release process or providing an out-of-cycle security update, depending on customer needs.
Microsoft then reiterated that the risk is limited since a customer would have to take multiple steps to make an attack successful.