CVE-2014-3343

Vulnerability

Cisco IOS XR version 5.1 contains a vulnerability in the DHCPv6 daemon that allows a remote, unauthenticated attacker to cause a denial of service (DoS) by sending a malformed DHCPv6 packet. The issue is identified by Cisco bug ID CSCuo59052 and is documented in reference [2].

Exploitation

An attacker can exploit this vulnerability by sending a specially crafted, malformed DHCPv6 packet to a device running Cisco IOS XR 5.1. No authentication or prior access is required; the attack is performed over the network [2].

Impact

Successful exploitation causes the DHCPv6 daemon on the targeted device to crash, resulting in a denial of service condition that disrupts DHCPv6 services. The device itself may continue to operate, but DHCPv6 functionality is lost [2].

Mitigation

As of the publication date (September 10, 2014), Cisco has not released a fixed version. Administrators are advised to monitor Cisco Security Advisories for updates. No workaround is documented in the available references [2][3].