SecurityFocus BUGTRAQ Mailing List: BugTraqLink Number One Link Number One Link 
Number Two Link Number Two  Link Number One Link Number One Link Number Two Link 
Number Two   
                          Entire Site Advisories Calendar Columnists Elsewhere 
                          Guest Feature Infocus Library Links Mailing Lists 
                          (all) -- BUGTRAQ -- FOCUS-IDS -- FOCUS-IH -- 
                          FOCUS-LINUX -- FOCUS-MS -- FOCUS-SUN -- FOCUS-VIRUS -- 
                          FORENSICS -- INCIDENTS -- PEN-TEST -- SEC JOBS -- SF 
                          NEWS -- VULN-DEV News Products Services Tools Vulns








             
             




                         BUGTRAQ ARCHIVE 

                        [ Message Index ] [ Thread Index ][ Reply ]
                        [ prev Msg by Date ][ next Msg by Date ]


                              To: BugTraq
                              Subject: SpeakFreely for Win <= 7.6a spoofed DoS
                              Date: Sep 22 2003 6:03PM
                              Author: Luigi Auriemma <aluigi altervista org>
                              Message-ID: 
                              <20030922180324.3be44ffc.aluigi@altervista.org>


#######################################################################

                             Luigi Auriemma

Application: SpeakFreely
             http://www.fourmilab.ch/speakfree/
             http://speak-freely.sourceforge.net
Versions:    <= 7.6a
Platforms:   Windows (Unix versions are NOT vulnerable)
Bug:         Remote crash caused by multiple spoofed connections
Risk:        Low
Author:      Luigi Auriemma
             e-mail: aluigi altervista org
             web:    http://aluigi.altervista.org


#######################################################################


1) Introduction
2) Bug
3) The Code
4) Fix


#######################################################################

===============
1) Introduction
===============


SpeakFreely is an interesting real-time voice chat application with
cryptographic support developed by John Walker and now the project will
be continued on Sourceforge by a group of programmers and fans.
The program is multiplatform, opensource and is also used as add-on of
ICQ.



#######################################################################

======
2) Bug
======


The bug exists only in the Windows version of the program (the project
at the moment is composed by 2 versions, one for Unix and another for
Windows).
Practically the resources of SpeakFreely can be easily consumed using
spoofed source IP addresses (the connections happen through UDP).

On Win98SE I have seen that less than 200 spoofed packets crash the
program remotely (about 160 packets exactly).

In fact after some packets, the following messages will be shown on the
victim:

"Cannot create transmit socket for host (x.x.x.x), error 10055.
No buffer space is available"

And then it will crash.


SpeakFreely has not a specific server and client; when it is launched
is both client and server at the same time, so everyone who uses the
Windows version can be DoSed by an attacker that has the ability to
send spoofed packets.

The important thing to fully complete the attack is its speed, however
are needed only 2 bytes for each packet so I think that this is not a
limit also on slow networks.




#######################################################################


===========
3) The Code
===========


Only for *nix:

http://aluigi.altervista.org/poc/sfdos.zip



#######################################################################

======
4) Fix
======


The project in this moment is in stall, so if it will be continued the
bug will be probably patched in the new version.



#######################################################################



--- 
Luigi Auriemma
http://aluigi.altervista.org







                  Want to link to this message? Use this URL: 
                  <http://www.securityfocus.com/archive/1/338433>
                  Disclaimer, Terms & Conditions


                  About this List


                  Featured Lists:

                  ARIS Users
                  bugtraq
                  bugtraq-es
                  bugtraq-french NEW
                  bugtraq-jp
                  firewalls
                  focus-ids
                  focus-ih
                  focus-linux
                  focus-ms
                  focus-sun
                  focus-unix-other
                  focus-virus
                  forensics
                  forensics-es
                  honeypots
                  incidents
                  libnet
                  pen-test
                  secevents
                  secpapers
                  secprog
                  sectools
                  secureshell
                  security-basics
                  security-management NEW
                  securityjobs
                  vpn
                  vuln-dev
                  webappsec

                  Newsletters:

                  sf-news
                  ms-secnews
                  linux-secnews


                  [ more . . . ]




                        Privacy Statement
                        Copyright © 1999-2003 SecurityFocus