This indicates an attack attempt to exploit a Denial of Service vulnerability in Linux NFv4 servers.
The vulnerability is due to an error when the vulnerable application handles maliciously crafted messages. A remote attacker may be able to exploit this to cause a denial of service condition on the affected system.
Linux Kernel Project Kernel prior to 4.12
Denial of Service: Remote attackers can crash vulnerable systems.
Apply the latest update from the vendor.