The IPv6 Router Advertisement Guard (RA-Guard) mechanism is commonly employed to mitigate attack vectors based on forged ICMPv6 Router Advertisement messages. Many existing IPv6 deployments rely on RA-Guard as the first line of defense against the aforementioned attack vectors. This document describes possible ways in which current RA- Guard implementations can be circumvented, and discusses possible mitigations.
You can download it from the following link: https://packetstormsecurity.com/files/download/101882/draft-gont-v6ops-ra-guard-evasion-00.txt
Source: https://packetstormsecurity.com/files/101882/IPv6-Router-Advertisement-Guard-RA-Guard-Evasion.html