SECURITY.NNOV: Outlook Express address book spoofing

From: 3APA3A (3APA3Aat_private)
Date: Tue Jun 05 2001 - 04:09:27 PDT

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    Hello bugtraq,
    
    sorry if this is already known - the bug is trivial.
    
    Issue                   :  Outlook  Express  address  book allows
                               messages to be intercepted by 3rd party
    Date Released           :  16 March 2001
    Vendor Notified         :  16 March 2001
    Author                  :  3APA3A <3APA3Aat_private>
    Affected                :  Outlook Exress 5.5SP1 and prior
    Discovered              :  18 December 2000 by 3APA3A
    Remotely Exploitable    :  Yes
    Vendor URL              :  http://www.microsoft.com
    SECURITY.NNOV advisories:  http://www.security.nnov.ru/advisories
    
    Description:
    
    It's possible for remote user to cause messages written for one e-mail
    address to be delivered to another e-mail address.
    
    Details:
    
    Outlook  Express has option "Automatically put people I reply to in my
    address  book".  Then  enabled,  this  option  causes  Outlook to make
    automatically  new  address  book  entries  mapping  NAME  of received
    message  to  e-mail  ADDRESS. Then message is composed Outlook Express
    checks address book for NAME and sets complete e-mail ADDRESS instead.
    
    Exploitation:
    
    Situation:  2  good  users  G1  and  G2 with addresses g1at_private and
    g2at_private  and  one  bad  user B, bat_private Imagine B wants to get
    messages G1 sends to G2. Scenario:
    
    1. B composes message with headers:
    
    From: "g2at_private" <bat_private>
    Reply-To: "g2at_private" <bat_private>
    To: G1 <g1at_private>
    Subject: how to catch you on Friday?
    
    and sends it to g1at_private
    
    2.  G1  receives  mail, which looks absolutely like mail received from
    g2at_private  and replies it. Reply will be received by B. In this case
    new  entry  is  created in address book pointing NAME "g2at_private" to
    ADDRESS bat_private
    
    3.  Now,  if  while  composing  new  message  G1 directly types e-mail
    address  g2at_private  instead  of  G2, Outlook will compose address as
    "g2at_private" <bat_private> and message will be received by B.
    
    Workaround:
    
    Disable  "Automatically  put  people  I  reply to in my address  book"
    option.
    
    
    Vendor:
    
    Microsoft was contacted, accepted problem and replied it's impossible
    to fix it until next IE 5.5 SP.
    
    Solution:
    
    No yet.
    
    
    -- 
    http://www.security.nnov.ru
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