Technical Information

Brief overview of the risk:
The most severe of these vulnerabilities could allow remote code execution if a user opens a specially crafted font file (such as a .fon file) in a network share, a UNC or WebDAV location, or an e-mail attachment. For a remote attack to be successful, a user must visit an untrusted remote file system location or WebDAV share and open the specially crafted font file, or open the file as an e-mail attachment.
Detailed Information on the risk:

An elevation of privilege vulnerability exists in the way that Windows kernel-mode drivers validate data supplied from user mode to kernel mode. An attacker who successfully exploited this vulnerability could run arbitrary code in kernel mode and take complete control of an affected system.

Further information on this exploit is available at : MS11-077