Re: Possible Intrusion Attempt?

[Gary Flynn <flynngn () jmu edu>]

Matt LaFelero wrote:
> I'm hoping someone here might be able to shed some light on this 
> situation..  
>
> Some of my users have been getting some interesting spam mail.  This is 
> the first time I've ever seen a spam mail do this.  When the user opens 
> the spam mail, all of a sudden, an Internet Explorer authentication 
> boxes pops up.  You know those that ask for username, password, and 
> domain.  
>
> Well, I run MS Proxy 2.0 here and the logon with a 2KPro machine is 
> integrated so the user never sees this box or has to enter his/her 
> password to get on the Web.  
>
> It's strange that this email triggers the authentication box.  What's 
> even weirder is that it populates the username for them, with weird 
> names.  The names always seem to change from spam mail to spam mail.  I've 
> seen iterations like fluff, skank, morton, taxiway.. you name it.
>
> It seems most of the emails are HTML, which can explain a lot.  None of 
> them had attachments.  From what I could gather it seems to attempting to 
> load a site.  We run Outlook 2000 with SP3 and all hotfixes.
>
> My question is, how is this happening and is it a threat?

I'd be interested in seeing the source of the mail message
to see if it contains script or a link to an image or other
material on a protected web server page. One could follow
that link, view source, and/or capture traffic and see what
is happening.

Internet Explorer will offer its local authentication credentials
(Windows or domain login) to web sites under some circumstances.
Internet Explorer's default security setting for login in the
Internet zone says IE will only automatically try to login in the
local Intranet zone. So unless they are exploiting a defect
in the zone boundaries, of which there have been quite a few,
they wouldn't seem to be able to collect credentials from
an Internet site.

--
Gary Flynn
Security Engineer - Technical Services
James Madison University

Please R.U.N.S.A.F.E.
http://www.jmu.edu/computing/runsafe


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