CVE-2011-4326

Severity: high (CVSS 7.1 v2.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 3.2% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2012-05-17 · updated 2026-06-16
Weakness: CWE-399

Description

The udp6_ufo_fragment function in net/ipv6/udp.c in the Linux kernel before 2.6.39, when a certain UDP Fragmentation Offload (UFO) configuration is enabled, allows remote attackers to cause a denial of service (system crash) by sending fragmented IPv6 UDP packets to a bridge device.

Affected products

Avaya 96X1 Ip Deskphone Firmware: from 6.0.0 through 6.6.0
Linux kernel: before 2.6.39 — fixed in 2.6.39

How to fix

Upgrade to a fixed version: Linux kernel 2.6.39. Check the vendor advisory for mitigations.

References

http://downloads.avaya.com/css/P8/documents/100156038
http://ftp.osuosl.org/pub/linux/kernel/v2.6/ChangeLog-2.6.39
http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git%3Ba=commit%3Bh=a9cf73ea7ff78f52662c8658d93c226effbbedde
http://www.openwall.com/lists/oss-security/2011/11/21/10
http://www.securityfocus.com/bid/50751
https://bugzilla.redhat.com/show_bug.cgi?id=682066
https://bugzilla.redhat.com/show_bug.cgi?id=755584
https://github.com/torvalds/linux/commit/a9cf73ea7ff78f52662c8658d93c226effbbedde
http://downloads.avaya.com/css/P8/documents/100156038
http://ftp.osuosl.org/pub/linux/kernel/v2.6/ChangeLog-2.6.39
http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git%3Ba=commit%3Bh=a9cf73ea7ff78f52662c8658d93c226effbbedde
http://www.openwall.com/lists/oss-security/2011/11/21/10

Get alerted when CVE-2011-4326 or the next vulnerability affects your stack