RE: Somebody exploiting (badly designed) yahoo service?

["Bojan Zdrnja" <Bojan.Zdrnja () LSS hr>]

Hi Alex :) 

> -----Original Message-----
> From: Aleksandar Milivojevic [mailto:alex () milivojevic org] 
> Sent: Wednesday, 12 May 2004 4:25 a.m.
> To: bugtraq () securityfocus com
> Subject: Somebody exploiting (badly designed) yahoo service?
>
> I don't know if this is something new, or something old.

I got the same thing couple of days ago.
It always uses the same link as you had, but it puts destination domain in
it, so the resulting link is like:

http://drs.yahoo.com/RECIPIENT_DOMAIN/NEWS/*http:// .....


> loads terra.html from the same site.  Downloading terra.html using wget,
> there's some more JavaScript (again after several empty screens) and some
> obfuscating code inside that I haven't analyzed in depth.

Terra.html file has some simple obfuscation. One obvious link that it opens
is at www.danni.com.
The other part is obfuscated by javascript.
After decoding this you get the following HTML code:

<iframe width=0 height=0
src="http://counter.spros.com/1/count.htm";></iframe>

Which essetianlly opens an invisible frame and goes to some counter site.
That count.htm is completely empty and is probably used to enumerate users
which click on this.

> Anybody seen this before?  Is this some kind of virus, worm, spyware, or
> simply a spam?  Looking at received headers of emails, it doesn't look
> like spam.  When I contacted the people who were listed as senders, they
> said they never sent it (but that they suspect they might be infected by
> some virus).

Same thing happened here. I didn't find any elements on that web page which
could auto run some things so I suspect on something else.
This would look to me like some kind of phishing, as it looks like it's at
least checking how many users clicked on this link - but it arrived from
legitimate users (headers confirm this) so it's really strange.

> I'll be contacting Yahoo about this (obviously, whatever they have at
> drs.yahoo.com isn't designed with security in mind), however I'm
> interested if anybody else saw/got this, and if he/she knows 
> what it is.

That's a pretty well known (and old) feature at Yahoo, which I don't know
why they provide - *a lot* of phishing e-mails I saw use this redirection
feature in an attempt to fool users.

I CC:ed this e-mail to incidents mailing list, I think it's more appropriate
there.

Cheers,

Bojan Zdrnja
CISSP


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