CVE-2015-2922 on Ubuntu 12.04 LTS (precise) - medium.
Description:
The ndisc_router_discovery function in net/ipv6/ndisc.c in the Neighbor Discovery (ND) protocol implementation in the IPv6 stack in the Linux kernel before 3.19.6 allows remote attackers to reconfigure a hop-limit setting via a small hop_limit value in a Router Advertisement (RA) message. It was discovered that the Linux kernel's IPv6 networking stack has a flaw that allows using route advertisement (RA) messages to set the 'hop_limit' to values that are too low. An unprivileged attacker on a local network could exploit this flaw to cause a denial of service (IPv6 messages dropped).