RE: OWA security

From: Martin K. Lee - XML Consulting (martin.lee_at_xmlconsulting.com.au)
Date: 01/13/04

  • Next message: Stefan Schmidt: "Trojan Port List" 
    Date: Tue, 13 Jan 2004 13:47:22 +1100
To: "Beverly Kittens" <beverlykittens@hotmail.com>

    Hi Beverly,

    If you are serious about security you shouldn't use HTTP for OWA access
    in the first place. HTTPS would help in this case (Well be aware of DoS
    though).

    Well if you are adding a separate web server into the network, I would
    suggest a firewall for separating the web server and the internal
    network. You may like to consider removing the connection of the PIX to
    the internal network and make a DMZ for the web server.

    My 2 cents...

    Martin K. Lee

    -----Original Message-----
    From: Beverly Kittens [mailto:beverlykittens@hotmail.com]
    Sent: Wednesday, December 17, 2003 12:43 AM
    To: MDunn@sscincorporated.com
    Cc: security-basics@securityfocus.com
    Subject: RE: OWA security

    Thanks Mike

    In fact we are using and ISA server. Proposed config looks like this.

    Internet
        |
    +------+ +------------------+
    | PIX |-----+----- | OWA Server |
    +------+ | +------------------+
       | |
       | +---------------+
       | | ISA Server |
       | +---------------+
       | |
    ----------------------------+---
    internal network |
                        +----------------------+
                        | Xchange server |
                        +----------------------+

    I'm trying to determine if this is a sensible architecture, and I'm
    still
    rather unclear about the function of the ISA server in this context.

    On a somewhat related topic: What stops an attacker compromising the
    web
    server then using it to attack an internal system? Port 80 is open from
    the
    Internet to the web server, and from the web server to the internal
    systems.
      Isn't this a huge security hole?

    >From: "Michael Dunn" <MDunn@sscincorporated.com>
    >To: "Beverly Kittens" <beverlykittens@hotmail.com>
    >CC: <security-basics@securityfocus.com>
    >Subject: RE: OWA security
    >Date: Mon, 15 Dec 2003 14:38:40 -0500
    >
    >
    >Check out isaserver.org.
    >
    >You may or may not be using ISA server as your firewall, but in either
    >case, there are several articles on 'best practices' for securing an
    >IIS/OWA server.
    >
    >Regards,
    >
    >-Mike
    >
    >-----Original Message-----
    >From: Beverly Kittens [mailto:beverlykittens@hotmail.com]
    >Sent: Monday, December 15, 2003 10:32 AM
    >To: security-basics@securityfocus.com
    >Subject: OWA security
    >
    >
    >
    >Hello list
    >
    >My company is currently implementing OWA to provide users with access
    >to email from any Internet machine. I'd like to see the OWA server in
    >a DMZ, but this is currently up for discussion. Sometimes operational
    >stuff gets in the way of security....
    >
    >Can anyone point me at a paper that describes the security implications

    >of OWA, particularly the network related issues please. I'd also be
    >interested to learn the difference between OWA and POP architecture.
    >
    >Thank you
    >
    >_________________________________________________________________
    >Use MSN Messenger to send music and pics to your friends
    >http://www.msn.co.uk/messenger
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  • Next message: Stefan Schmidt: "Trojan Port List"

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