This indicates an attack attempt to exploit a Denial Of Service vulnerability in Ivanti Endpoint Manager.
The vulnerability is due to an error when the vulnerable software handles a maliciously crafted request. A remote attacker may be able to exploit this to cause memory exhaustion on a vulnerable server.
Ivanti Endpoint Manager 2018.3 and below
Denial of Service: Remote attackers can crash vulnerable systems.
Currently we are unaware of any vendor supplied patch for this issue.