Cisco Web Security Appliance Web Proxy Memory Exhaustion Denial of Service 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:
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.
Fixed Releases
Customers are advised to upgrade to an appropriate release as indicated in the following table:
| Cisco AsyncOS Software Major Release | First Fixed Release |
|---|---|
| Prior to 9.1 | Migrate to 10.1.3-054 or later |
| 9.1 | Migrate to 10.1.3-054 or later |
| 10.1 | 10.1.3-054 |
| 10.5 | 10.5.2-072 |
| 11.0 | 11.5.0-614 |
| 11.5 | Not vulnerable |
In most cases, the software can be upgraded over the network by using the System Upgrade options in the web interface of the WSA. To upgrade a device by using the web interface:
- Choose System Administration > System Upgrade.
- Click Upgrade Options.
- Choose Download and Install.
- Choose the release to upgrade to.
- In the Upgrade Preparation area, choose the appropriate options.
- Click Proceed to begin the upgrade. A progress bar displays the status of the upgrade.
After the upgrade is complete, the device reboots.
from Cisco Security Advisory https://ift.tt/2MKDwAe