RE: [Full-disclosure] Anonymous Web Attacks via DedicatedMobileServices

[Bojan Zdrnja]

> -----Original Message-----
> From: full-disclosure-bounces@lists.grok.org.uk
> [mailto:full-disclosure-bounces@lists.grok.org.uk] On Behalf
> Of Morning Wood
> Sent: Wednesday, 20 July 2005 5:02 a.m.
> To: Petko Petkov; bugtraq@securityfocus.com
> Cc: full-disclosure@lists.grok.org.uk
> Subject: Re: [Full-disclosure] Anonymous Web Attacks via
> DedicatedMobileServices
>
> google's language translation also does this..
> http://ipchicken.com
> http://translate.google.com/translate?u=http://ipchicken.com

Regarding Google - yes, if you log only connections.
However, when you use translate.google.com service, Google will add a new
header in the HTTP request:

X-Forwarded-For: <IP address>

All proxy servers should add this header, even in the case of multiple
proxying, in which case all IP addresses should be listed under this header.

For Apache, there is even a mod_extract_forwarded module which should change
the connection so it looks like it's coming from the IP behind the proxy
server.


I don't see any special risk with this, even for mobile devices (mentioned
in the original post) -- a proxy just does it's job, no matter which proxy
it is. If Google keeps logs, even if you don't save X-Forwarded-For header
and parse them, you can find out who visited the web page, if it goes to
investigation.

Cheers,

Bojan

[Alexander Klimov]

On Sun, 24 Jul 2005, Bojan Zdrnja wrote:
> Regarding Google - yes, if you log only connections.
> However, when you use translate.google.com service, Google will add a new
> header in the HTTP request:
>
> X-Forwarded-For: <IP address>
>
> All proxy servers should add this header, even in the case of multiple
> proxying, in which case all IP addresses should be listed under this header.
>
> For Apache, there is even a mod_extract_forwarded module which should change
> the connection so it looks like it's coming from the IP behind the proxy
> server.
>

If you do assume that x-forwarded-for is always genuine then you will
have problems when somebody with direct connection adds
x-forwarded-for to confuse you (this is very similar to email
headers).

BTW: I don't sure that it is that important for real attackers -- most
of them are likely to use owned hosts anyway.

--
Regards,
ASK