Tag: sccp

Cisco: CUCM DoS Vulnerabilities

Cisco Unified Communications Manager (formerly Cisco CallManager) contains multiple denial of service (DoS) vulnerabilities that if exploited could cause an interruption of voice services. The Session Initiation Protocol (SIP), Skinny Client Control Protocol (SCCP) and Computer Telephony Integration (CTI) Manager services are affected by these vulnerabilities.

To address these vulnerabilities, Cisco has released free software updates for select Cisco Unified Communications Manager versions. There is a workaround for of one the vulnerabilities.

The following products are affected by vulnerabilities that are described in this advisory:

* Cisco Unified Communications Manager 4.x
* Cisco Unified Communications Manager 5.x
* Cisco Unified Communications Manager 6.x
* Cisco Unified Communications Manager 7.x

Administrators can mitigate the SCCP- and SIP-related vulnerabilities by implementing filtering on screening devices to permit access to TCP ports 2000 and 2443, and TCP and UDP ports 5060 and 5061 only from networks that require SCCP and SIP access to Cisco Unified Communications Manager appliances.

It is possible to mitigate the CTI Manager vulnerability by disabling the CTI Manager service t is not necessary; however, this workaround will interrupt applications that reply on the CTI Manager service. Administrators can also mitigate the vulnerability by implementing filtering on screening devices to permit access to TCP port 2748 only from networks that require access to the CTI Manager service.

This advisory is posted at http://www.cisco.com/warp/public/707/cisco-sa-20100303-cucm.shtml

Cisco FWSM SCCP Inspection DoS Vulnerability

A vulnerability exists in the Cisco Firewall Services Module (FWSM) for the Cisco Catalyst 6500 Series Switches and Cisco 7600 Series Routers that may cause the Cisco FWSM to reload after processing a malformed Skinny Client Control Protocol (SCCP) message. The vulnerability exists when SCCP inspection is enabled.

Cisco has released free software updates that address this vulnerability.

All non-fixed 4.x versions of Cisco FWSM Software are affected by this vulnerability if SCCP inspection is enabled. SCCP inspection is enabled by default.

To check if SCCP inspection is enabled, issue the show service-policy | include skinny command and confirm that the command returns output. Example output follows:

fwsm#show service-policy | include skinny
Inspect: skinny , packet 0, drop 0, reset-drop 0

If SCCP inspection is not required, this vulnerability can be mitigated by disabling it. Administrators can disable SCCP inspection by issuing the no inspect skinny command in class configuration sub-mode within the policy map configuration. If SCCP inspection is required, there are no workarounds.

Cisco has released free software updates that address this vulnerability. Prior to deploying software, customers should consult their maintenance provider or check the software for feature set compatibility and known issues specific to their environment.

This advisory is posted at http://www.cisco.com/warp/public/707/cisco-sa-20100217-fwsm.shtml