Cisco devices that are running affected Cisco IOS Software versions are vulnerable when HTTP ALG inspection or Cisco IOS Content Filtering is configured under the ZBFW.
To verify whether the HTTP ALG inspection under the ZBFW is configured on a device use the show running-config
command. If the service policy that is attached to any zone contains a policy map that contains the command service-policy http name
then the device is configured for HTTP ALG. The following is the output from the show running-config
command executed on a device running Cisco IOS Software that has the HTTP ALG inspection enabled under the ZBFW configuration:
< output removed for brevity >
policy-map type inspect in->out
class type inspect filtered-hosts
service-policy http http_bad
zone security inside
zone security outside
zone-pair security in-to-out source inside destination outside
service-policy type inspect in->out
< output removed for brevity >
To verify whether Cisco IOS Content Filtering under the ZBFW is configured on a device use the show policy-map type inspect zone-pair urlfilter | include URL Filtering
privileged EXEC command and check for output. A blank line indicates that the feature is not enabled. Output with URL Filtering is in
indicates the device is configured with Cisco IOS Content Filtering under ZBFW. The following is the output from the show policy-map type inspect zone-pair urlfilter | include URL Filtering
command executed on a device running Cisco IOS Software that has Cisco IOS Content Filtering enabled under the ZBFW configuration:
ios-fw#show policy-map type inspect zone-pair urlfilter | include URL Filtering
URL Filtering is in
Cisco IOS Content Filtering using ip inspect
and ip urlfilter
commands are not affected.
To determine the Cisco IOS Software release that is running on a Cisco product, administrators can log in to the device and issue the show version command to display the system banner. The system banner confirms that the device is running Cisco IOS Software by displaying text similar to "Cisco Internetwork Operating System Software" or "Cisco IOS Software." The image name displays in parentheses, followed by "Version" and the Cisco IOS Software release name. Other Cisco devices do not have the show version command or may provide different output.
The following example identifies a Cisco product that is running Cisco IOS Software Release 15.0(1)M1 with an installed image name of C3900-UNIVERSALK9-M:
Router> show version
Cisco IOS Software, C3900 Software (C3900-UNIVERSALK9-M), Version 15.0(1)M1, RELEASE SOFTWARE (fc1)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2009 by Cisco Systems, Inc.
Compiled Wed 02-Dec-09 17:17 by prod_rel_team
!--- output truncated
Additional information about Cisco IOS Software release naming conventions is available in "White Paper: Cisco IOS and NX-OS Software Reference Guide" at http://www.cisco.com/web/about/security/intelligence/ios-ref.html.
Cisco IOS XR Software is not affected by this vulnerability.
Cisco IOS XE Software is not affected by this vulnerability.
No other Cisco products are currently known to be affected by this vulnerability.