This indicates an attack attempt against a Denial of Service vulnerability in Microsoft Windows NFS Server.
The vulnerability is caused by an error when an invalid NFS file operation is requested on a read-only share directory. It allows a remote attacker to cause a denial-of-service condition to a vulnerable server.
Microsoft Windows Server 2008 R2 for Itanium-based Systems
Microsoft Windows Server 2008 R2 for x64
Microsoft Windows Server 2012
Denial of Service: Remote attackers can crash vulnerable systems.
Apply the most recent upgrade or patch from the vendor.