cisco-sa-cucm-rce-bWNzQcUm · Critical · Published · Updated
A vulnerability in multiple Cisco Unified Communications and Contact Center Solutions products could allow an unauthenticated, remote attacker to execute arbitrary code on an affected device. This vulnerability is due to the improper processing of user-provided data that is being read into memory. An attacker could exploit this vulnerability by sending a crafted message to a listening port of an affected device. A successful exploit could allow the attacker to execute arbitrary commands on the underlying operating system with the privileges of the web services user. With access to the underlying operating system, the attacker could also establish root access on the affected device. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability. This advisory is available at the following link:https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-cucm-rce-bWNzQcUm
There are no workarounds that address this vulnerability. However, a mitigation is available.
Establish access control lists (ACLs) on intermediary devices that separate the Cisco Unified Communications or Cisco Contact Center Solutions cluster from users and the rest of the network to allow access only to the ports of deployed services. The port list will vary depending on the voice products and services in use. Some ports are ephemeral and will change after a restart.
While this mitigation has been deployed and was proven successful in a test environment, customers should determine the applicability and effectiveness in their own environment and under their own use conditions. Customers should be aware that any workaround or mitigation that is implemented may negatively impact the functionality or performance of their network based on intrinsic customer deployment scenarios and limitations. Customers should not deploy any workarounds or mitigations before first evaluating the applicability to their own environment and any impact to such environment.