This indicates an attack attempt to exploit a Denial of Service vulnerability in Digium Asterisk.
The vulnerability is due to an error when the vulnerable module handles malicious SCCP requests. A remote attacker may be able to exploit this to cause a denial of service condition on the affected system.
Digium Certified Asterisk prior to 15.1.3
Digium Certified Asterisk prior to 14.7.3
Digium Certified Asterisk prior to 13.18.3
Digium Certified Asterisk prior to 13.13-cert8
Denial of Service: Remote attackers can crash vulnerable systems.
Apply the most recent upgrade or patch from the vendor.