A Cisco device running an affected version of Cisco IOS Software or Cisco IOS XE Software release and has IPv6 enabled will show interfaces with assigned IPv6 addresses when the show ipv6 interface brief
command is issued.
The show ipv6 interface brief
command will produce an error message if the running version of Cisco IOS Software or Cisco IOS XE Software release does not support IPv6, or will not show any interfaces with IPv6 addresses if IPv6 is disabled. The system is not vulnerable in either scenario.
The following example shows the output from the show ipv6 interface brief
command issued on a device running Cisco IOS Software enabled for IPv6:
router>show ipv6 interface brief
The IPv6 protocol is enabled if the interface configuration command ipv6 address <IPv6 address>
or ipv6 enable
is present in the configuration; however, both may be present. The following examples shows a vulnerable configuration with both present:
ipv6 address 2001:0DB8:C18:1::/64 eui-64
A device running Cisco IOS Software or Cisco IOS XE Software with IPv6 enabled on a physical or logical interface is vulnerable even if ipv6 unicast-routing
is globally disabled (that is, the device is not routing IPv6 packets).
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 15.2(4)M5 with an installed image name of C3900-UNIVERSALK9-M:
Router> show version
Cisco IOS Software, C3900 Software (C3900-UNIVERSALK9-M), 15.2(4)M5, RELEASE SOFTWARE (fc2)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2013 by Cisco Systems, Inc.
Compiled Fri 13-Sep-13 16:44 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.
The following products are not affected by this vulnerability:
- Cisco IOS XR Software
- Cisco NX-OS Software
- Cisco ASA Software
No other Cisco products are currently known to be affected by this vulnerability.