CVE-2012-4444 on Ubuntu 12.04 LTS (precise) - medium.
Description:
The ip6_frag_queue function in net/ipv6/reassembly.c in the Linux kernel before 2.6.36 allows remote attackers to bypass intended network restrictions via overlapping IPv6 fragments. Zhang Zuotao discovered a bug in the Linux kernel's handling of overlapping fragments in ipv6. A remote attacker could exploit this flaw to bypass firewalls and initial new network connections that should have been blocked by the firewall.