[pedantic]

Linky

Critical: Extremely critical
Impact: System access
Where: From remote
Solution Status: Unpatched

A vulnerability has been reported in Microsoft Office, which can be exploited by malicious people to compromise a user's system.

The vulnerability is caused due to an unspecified error when handling strings and can be exploited to cause a memory corruption.

Successful exploitation allows execution of arbitary code.

NOTE: According to Microsoft, the vulnerability is currently being actively exploited via Excel, but other Office applications may also be affected.

Solution:
Do not open untrusted Office documents