Re: More Internet Explorer zone confusion

From: Walt Armour (waltat_private)
Date: Mon Mar 08 1999 - 00:18:10 PST

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    I would agree that these are still issues but there is a difference
    between them and the original problem.
    
    With the original problem any site could redirect you to a site and make
    it look like Local Intranet simply by using the 'http://031713501415/'
    format.
    
    With these two new issues someone must have direct knowledge about your
    machine's configuration or have direct access to your machine in order to
    make a not-quite-too-common configuration change.  If either of these
    situations occurs then the safety level of my browser will quickly become
    the least of my worries.  :)
    
    IMO Microsoft is right in saying that the problems are (marginally)
    different.  Whether or not their method for determining "local intranet"
    is right is a completely different subject.
    
    walt
    
    
    On Fri, 5 Mar 1999, Jim Paris wrote:
    
    > Even after the patch described in Microsoft Security Bulletin MS98-016
    > (http://www.microsoft.com/security/bulletins/ms98-016.asp), IE4 still
    > has big problems with distinguishing between sites that belong in the
    > "Internet Zone" and sites that belong in the "Local Intranet Zone".
    >
    > MS98-016 dealt with addresses such as http://031713501415/, which
    > resolve to Internet hosts but are categorized as being in the "Local
    > Intranet Zone".
    >
    > I've found two cases where the problem still exists.  The first is when
    > the user has the "Domain Suffix Search Order" in the TCP/IP DNS settings
    > set to include domains such as "com".  In that case, the address
    > 	http://microsoft/
    > will retrieve the page at
    > 	http://microsoft.com/
    > but it will be considered to be in the "Local Intranet Zone".
    >
    > The second case occurs when a host has an assigned alias in the hosts
    > table (C:\WINDOWS\HOSTS).  A host table entry such as:
    > 	207.46.131.13	hello
    > will cause the URL
    > 	http://hello/
    > to retrieve the page at http://207.45.131.13/, but (yep, you guess it)
    > Internet Explorer still considers it to be in the "Local Intranet Zone".
    >
    > This has security implications, since settings for the Local Intranet
    > Zone may be (and, by default, ARE) less secure than those for the
    > Internet Zone.
    >
    >
    > And the funny part?  Microsoft's response when I told them this:
    >
    > --8<---cut here-----------------------------------------
    >
    > Hi Jim -
    >
    > Had a talk with one of the IE developers, and this behavior is correct.
    > Here's why: it's impossible to tell from an IP address whether it's internal
    > or external.  100.100.100.100, or any other address, could be either
    > internal or external, depending on whether you're behind a firewall or not.
    > That means that IE has to rely on the URL.  By convention, an URL that does
    > not end with a "dot-something" (.com, .edu, .gov, etc) is assumed to be an
    > internal site.  I'm told that this is how all web browsers make the
    > distinction.  You have to make specific reconfigurations to allow the
    > dotless URLs to resolve externally. Thanks,
    >
    > Secureat_private
    >
    > --8<---cut here-----------------------------------------
    >
    >
    > "This behavior is correct"?!?!?!  Give me a break.  They obviously
    > didn't think so when they released the MS98-016 bulletin.
    >
    >
    > Jim Paris
    > jimat_private
    >
    



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