Bug 442410

Summary:	Kernel : net: acceptation of overlapping ipv6 fragments (CVE-2012-4444)
Product:	Gentoo Security	Reporter:	Agostino Sarubbo <ago>
Component:	Kernel	Assignee:	Gentoo Security <security>
Status:	RESOLVED FIXED
Severity:	normal	CC:	kernel
Priority:	Normal
Version:	unspecified
Hardware:	All
OS:	Linux
Whiteboard:	[<2.6.36]
Package list:		Runtime testing required:	---

Description Agostino Sarubbo gentoo-dev

2012-11-09 09:56:23 UTC

From https://bugzilla.redhat.com/show_bug.cgi?id=874835 :

Accepting overlapping fragmented ipv6 packets can lead to Operating Systems (OS) fingerprinting, 
IDS/IPS insertion/evasion, firewall evasion.
Do not accept such packets.

Linux kernel upstream fix:
http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=70789d7052239992824628db8133de08dc78e593

References:
http://tools.ietf.org/rfc/rfc5722.txt
https://media.blackhat.com/bh-eu-12/Atlasis/bh-eu-12-Atlasis-Attacking_IPv6-WP.pdf