This indicates an attack attempt against a Denial of Service Vulnerability in IBM Tivoli Storage Manager FastBack Server.
The vulnerability is caused by an improper validation of user supplied data when the vulnerable application handles a maliciously crafted request. A remote attacker may be able to exploit this to cause a denial of service condition on affected systems.
IBM Tivoli Storage Manager FastBack 220.127.116.11 through 18.104.22.168.
IBM Tivoli Storage Manager FastBack 5.5.
Denial of Service: Remote attackers can crash vulnerable systems.
Apply the most recent upgrade or patch from the vendor