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: https://www.cisco.com/c/en/us/products/end-user-license-agreement.html
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: https://www.cisco.com/c/en/us/support/web/tsd-cisco-worldwide-contacts.html
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.
Customers are advised to upgrade to an appropriate fixed firmware release as indicated in the following table:
|Cisco IP Phone Model
||Cisco Bug ID
||First Fixed Release
|IP Phone 7811, 7821, 7841, 7861 Desktop Phones
|IP Phone 8811, 8841, 8845, 8851, 8861, 8865 Desktop Phones
|Unified IP Conference Phone 8831
|Wireless IP Phone 8821, 8821-EX
To download the Cisco IP Phone firmware from the Software Center on Cisco.com, do the following:
- Click Browse all.
- Choose Collaboration Endpoints > IP Phones.
- Choose a specific product from the right pane of the product selector.
- Choose a release from the left pane of the product page.