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:
Additionally, 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:
Customers 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.
This vulnerability has been corrected in Cisco IOS XR Software Release 6.3.2 and later.
Software maintenance upgrades (SMUs) for Cisco Aggregation Services Router (ASR) 9000 Series have also been made available that address this vulnerability.
: An SMU including a partial fix named "asr9k-px-5.3.4.CSCvh49341.tar" was made available for a short time for Cisco IOS XR Software Release 5.3.4. After additional testing, this was verified to be an incomplete fix. Cisco recommends that customers who might have installed this SMU uninstall it and install the new SMU containing the complete fix referenced in the table.
Customers using a Cisco IOS XR platform other than ASR 9000 Series Routers, or running a Cisco IOS XR Software Release for which no SMU is listed in the previous table, are advised to upgrade the IOS XR Software or open a support case to evaluate upgrade options.
Cisco IOS XR Software can be downloaded from the Software Center on Cisco.com by navigating to Downloads Home > Products > Routers > Service Provider Edge Routers or Service Provider Core Routers, selecting the appropriate product, and selecting IOS XR Software.
The SMUs for Cisco ASR 9000 Series Routers can be downloaded from the Software Center on Cisco.com by navigating to Downloads Home > Products > Routers > Service Provider Edge Routers > ASR 9000 Series Aggregation Services Routers > ASR 9xxx Router > Software on Chassis > IOS XR Software Maintenance Upgrades (SMU).