CVE-2019-1721

A vulnerability in the phone book feature of Cisco Expressway Series and Cisco TelePresence Video Communication Server (VCS) could allow an authenticated, remote attacker to cause the CPU to increase to 100% utilization, causing a denial of service (DoS) condition on an affected system. The vulnerability is due to improper handling of the XML input. An attacker could exploit this vulnerability by sending a Session Initiation Protocol (SIP) message with a crafted XML payload to an affected device. A successful exploit could allow the attacker to exhaust CPU resources, resulting in a DoS condition. Manual intervention may be required to recover the device. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability. Mitigation options that address this vulnerability are available. This advisory is available at the following link: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190417-es-tvcs-dos ["https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190417-es-tvcs-dos"]