![](https://tools.cisco.com/security/center/images/blue-square.png)
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:X/RL:X/RC:X
-
A vulnerability in the Session Initiation Protocol (SIP) UDP throttling process of Cisco Unified Communications Manager (Cisco Unified CM) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device.
The vulnerability is due to insufficient rate limiting protection. An attacker could exploit this vulnerability by sending the affected device a high rate of SIP messages. An exploit could allow the attacker to cause the device to reload unexpectedly. The device and services will restart automatically.
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://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170419-ucm
-
Vulnerable Products
This vulnerability affects Cisco Unified Communications Manager (CallManager) releases prior to the first fixed release. For information about fixed releases, see the Fixed Software section of this advisory.
To determine the release of Cisco Unified Communications Manager running on a device, administrators can use the show version active command in the CLI of the device.
The following example shows the output from a device that is running Release 11.5(1) of the service:
admin: show version active Active Master Version: 11.5.1.10000-4 Active Version Installed Software Options: No Installed Software Options Found.
Products Confirmed Not Vulnerable
No other Cisco products are currently known to be affected by this vulnerability.
Cisco has confirmed that Cisco Unified CM Releases 9.x and earlier are not affected by this vulnerability.
-
Cisco has released free software updates that address the vulnerability described in this advisory. Customers may only install and expect support for software versions and feature sets for which they have purchased a license. By installing, downloading, accessing, or otherwise using such software upgrades, customers agree to follow the terms of the Cisco software license:
http://www.cisco.com/en/US/docs/general/warranty/English/EU1KEN_.htmlAdditionally, customers may only download software for which they have a valid license, procured from Cisco directly, or through a Cisco authorized reseller or partner. In most cases this will be a maintenance upgrade to software that was previously purchased. Free security software updates do not entitle customers to a new software license, additional software feature sets, or major revision upgrades.
When considering software upgrades, customers are advised to regularly consult the advisories for Cisco products, which are available from the Cisco Security Advisories and Alerts page, to determine exposure and a complete upgrade solution.
In all cases, customers should ensure that the devices to be upgraded contain sufficient memory and confirm that current hardware and software configurations will continue to be supported properly by the new release. If the information is not clear, customers are advised to contact the Cisco Technical Assistance Center (TAC) or their contracted maintenance providers.
Customers Without Service Contracts
Customers who purchase directly from Cisco but do not hold a Cisco service contract and customers who make purchases through third-party vendors but are unsuccessful in obtaining fixed software through their point of sale should obtain upgrades by contacting the Cisco TAC:
http://www.cisco.com/en/US/support/tsd_cisco_worldwide_contacts.htmlCustomers should have the product serial number available and be prepared to provide the URL of this advisory as evidence of entitlement to a free upgrade.
Fixed Releases
Customers are advised to install an appropriate fixed release as indicated in this section.
The following list indicates the first minor release that includes the fix for this this vulnerability:- 10.5.2.14900-16
- 11.0.1.23900-5
- 11.5.1.12900-21
-
The Cisco Product Security Incident Response Team (PSIRT) is not aware of any public announcements or malicious use of the vulnerability that is described in this advisory.
-
This vulnerability was found during the resolution of a support case.
-
To learn about Cisco security vulnerability disclosure policies and publications, see the Security Vulnerability Policy. This document also contains instructions for obtaining fixed software and receiving security vulnerability information from Cisco.
-
Version Description Section Status Date 1.1 Updated the first fixed release number for Release 11.5.1.12900. Fixed Software Final 2017-April-21 1.0 Initial public release. — Final 2017-April-19
-
THIS DOCUMENT IS PROVIDED ON AN "AS IS" BASIS AND DOES NOT IMPLY ANY KIND OF GUARANTEE OR WARRANTY, INCLUDING THE WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR USE. YOUR USE OF THE INFORMATION ON THE DOCUMENT OR MATERIALS LINKED FROM THE DOCUMENT IS AT YOUR OWN RISK. CISCO RESERVES THE RIGHT TO CHANGE OR UPDATE THIS DOCUMENT AT ANY TIME.
A standalone copy or paraphrase of the text of this document that omits the distribution URL is an uncontrolled copy and may lack important information or contain factual errors. The information in this document is intended for end users of Cisco products.