Microsoft Office is prone to a vulnerability that lets attackers execute arbitrary code. An attacker can exploit this issue by enticing a legitimate user to use the vulnerable application to open a file from a network share location that contains a specially crafted Dynamic Link Library (DLL) file.
Block external access at the network boundary, unless external parties require service.
If global access isn't needed, filter access to the affected computer at the network boundary. Restricting access to only trusted computers and networks might greatly reduce the likelihood of successful exploits.
Run all software as a nonprivileged user with minimal access rights.
To reduce the impact of latent vulnerabilities, always run nonadministrative software as an unprivileged user with minimal access rights.
Vendor updates are available. Please see the references for details.