Cisco IOS 12.1YD, 12.2T, 12.3 and 12.3T, when configured for the IOS Telephony Service (ITS), CallManager Express (CME) or Survivable Remote Site Telephony (SRST), allows remote attackers to cause a denial of service (device reboot) via a malformed packet to the SCCP port.
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A4849
https://exchange.xforce.ibmcloud.com/vulnerabilities/18956