RE: E-Mail gateway on IIS.

From: Beauford, Jason (jbeauford_at_EightInOnePet.com)
Date: 06/13/05

  • Next message: martin: "Re: RunAs"
    Date: Mon, 13 Jun 2005 15:57:27 -0400
    To: <focus-ms@securityfocus.com>
    
    

    An issue I can think of is this:

    Say that Email gateway has a local quarantine, as does Brightmail, and
    is using LDAP authentications for AD users to log on to their local
    quarantine boxes. If the IIS server is compromised (very common
    nowadays) then it would be trivial to capture those unencrypted LDAP
    authentications and essentially the hacker would have valid AD usernames
    and passwords.

    Also: Since it is an email gateway, (is this an Exchange backend?) then
    it probably has relay permissions on your backend mail server. If IIS
    is comp'd then it would be trivial for a hacker to use your Backend mail
    server to relay mail.

    I can imagine a situation where your IIS is hijacked or modded to host
    Phishing scams and your backend mail server is used to send out the
    initial phishing emails. This of course would set off too many red
    flags for it to be viable, but it is still possible.

    I'd put them on separate boxes with both boxes in the DMZ and a pinhole
    for port 25. I'm sure you know not to make either a part of your Domain
    (if you're in an AD environment).

    With regards to budgets: Figure out the cost of mitigating the risk
    versus the cost of an intrusion where confidential corporate data is
    stolen (a recent popular trend - Motorola, Citibank etc.). I'm sure the
    cost of a separate server plus the cost of maintenance < the cost of the
    intrusion.

    Just my $.02.

    JMB

    -----Original Message-----
    From: Meni Milstein [mailto:meni@kdm.co.il]
    Sent: Monday, June 13, 2005 1:04 PM
    Cc: focus-ms@securityfocus.com
    Subject: RE: E-Mail gateway on IIS.

    You are looking at it from two perspectives. (or at least - you should
    be).

    One machine is one point of attack - meaning if the machine is
    successfully attacked then both services are down... as Burton implies.

    Two different machines are more costly to maintain and if you say that
    you run both sevrices on the same machine I assume that they have the
    same OS... which means that securing them would just about be the same
    Job (aside from securing the actual protocols themselves...)

    I would go with two separate machines if I had the budjet... always
    cooler to have at least 50% of services running in case a of a real
    attack. But I see no real issue that can arise from running the services
    on one machine. Of course - this machine should be strong enough to
    support both services. If your mail GW scans outgoing mails for viruses,
    then I guess, depending on the size of your org, the server may need to
    handle loads... in which case you should consider seperating the
    services.

    In terms of security - I see no problem.

    Good luck.

    Meni Milstein
    http://www.lcs-guides.com

    -----Original Message-----
    From: Burton Strauss [mailto:BStrauss3@comcast.net]
    Sent: Monday, June 13, 2005 6:38 PM
    To: 'Jitendra Kalyankar'; focus-ms@securityfocus.com
    Subject: RE: E-Mail gateway on IIS.

    Two separate boxes are two separate points of attack. One box is a
    single point, slightly more attractive to the bad guy.

    Two boxes mean both require the same OS patches and basic OS security
    (hardening).

    Either way, each service needs to be secured individually.

    It might be less disruptive to be able to reboot separately, or it may
    be easier to only need one reboot.

    Probably can go both ways depending on your personal preference.

    -----Burton

    -----Original Message-----
    From: Jitendra Kalyankar [mailto:jitendra.kalyankar@gmail.com]
    Sent: Monday, June 13, 2005 6:27 AM
    To: focus-ms@securityfocus.com
    Subject: E-Mail gateway on IIS.

    MS Gurus -

    I have on question about the e-mail gateway. I am working with this
    company where company has webserver as well as E-Mail gateway on the
    same server. Let me know if this will create any security risks. In
    other words is it recommanded that you need to have seperate webserver
    and e-mail gateway servers.

    Any inputs on this are highly appreciated.

    --
    Thanks,
    Jitendra Kalyankar
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  • Next message: martin: "Re: RunAs"

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