This indicates an attack attempt to exploit an Authentication Bypass Vulnerability in Ivanti Avalanche.
The vulnerability is due to lack of authentication for certain functionality. A remote attacker can exploit this vulnerability by sending a crafted request to the target server. Successful exploitation could result in access control policy bypass, including arbitrary admin account creation.
Ivanti Avalanche prior to 6.3.3
System Compromise: Remote attackers can gain control of vulnerable systems.
Apply the most recent upgrade or patch from the vendor.