Cisco IOS and IOS XE Software DHCPv6 Relay Denial of Service Vulnerability

A vulnerability in the DHCP version 6 (DHCPv6) relay feature of Cisco IOS and IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload.

The vulnerability is due to insufficient validation of DHCPv6 relay messages. An attacker could exploit this vulnerability by sending a crafted DHCPv6 relay message to an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a denial of service (DoS) condition.

Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.

This advisory is available at the following link:

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20160323-dhcpv6[“https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20160323-dhcpv6”]

This advisory is part of the March 23, 2016, release of the Cisco IOS and IOS XE Software Security Advisory Bundled Publication, which includes six Cisco Security Advisories that describe six vulnerabilities. All the vulnerabilities have a Security Impact Rating of “High.” For a complete list of advisories and links to them, see Cisco Event Response: Semiannual Cisco IOS and IOS XE Software Security Advisory Bundled Publication[“http://www.cisco.com/c/en/us/about/security-center/event-response/cisco-erp-march-2016.html”].