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Re: Google's robot.txt handling
From: Christian Sciberras <uuf6429 () gmail com>
Date: Tue, 11 Dec 2012 23:53:12 +0100

If you ask me, it's a stupid idea. :)

I prefer to know where I am with a service; and (IMHO) I would prefer to
query (occasionally) Google for my CC instead of waiting for someone to
start taking funds off it.
Hiding it only provides a false sense of security - it will last until
someone finds the service leaking out CCs.

This is especially the case with robots.txt. Can someone on the list please
define a "good web crawler"?
There's plenty of crawlers out there, most are relatively unknown.... how
will we know which to trust?

I think the problem here is that people are plain stupid and throw in
direct entries inside robots.txt, whereas they should be sending wildcard
entries.
Couple that with actually protecting sensitive areas, and it's a pretty
good defence.

On a side note, someone already said this, but I'll repeat it for effect:
don't thrown in anything on the Net which you're not prepared to protect.
If a control panel should
not be accessible to the general public, consider restricting access by IP
and similar measures. Even a personal certificate is a valid layer of
defence...


Chris.



On Tue, Dec 11, 2012 at 10:38 PM, Jeffrey Walton <noloader () gmail com> wrote:

On Tue, Dec 11, 2012 at 4:11 PM, Mario Vilas <mvilas () gmail com> wrote:
I think we can all agree this is not a vulnerability. Still, I have yet
to
see an argument saying why what the OP is proposing is a bad idea. It
may be
a good idea to stop indexing robots.txt to mitigate the faults of lazy or
incompetent admins (Google already does this for many specific search
queries) and there's not much point in indexing the robots.txt file for
legitimate uses anyway.
I kind of agree here. The information is valuable for the
reconnaissance phase of an attack, buts its not a vulnerability per
se. But what is to stop the attacker from fetching it himself/herself
since its at a known location for all sites? In this case, Google
would be removing aggregated search results (which means the attacker
would have to compile it himself/herself).

Google removed other interesting searches, such as social security
numbers and credit card numbers (or does not provide them to the
general public).

Jeff

On Tue, Dec 11, 2012 at 2:01 PM, Scott Ferguson
<scott.ferguson.it.consulting () gmail com> wrote:

If I understand the OP correctly, he is not stating that listing
something
in robots.txt would make it inaccessible, but rather that Google
indexes
the robots.txt files themselves,

<snipped>

Well, um, yeah - I got that.

So you are what, proposing that moving an open door back a few
centimetres solves the (non) problem?

Take your proposal to it's logical extension and stop all search engines
(especially the ones that don't respect robots.txt) from indexing
robots.txt. Now what do you do about Nutch or even some perl script that
anyone can whip up in 2 minutes?

Security through obscurity is fine when couple with actual security -
but relying on it alone is just daft.

Expecting to world to change so bad habits have no consequence is
dangerously naive.

I suspect you're looking to hard at finding fault with Google - who are
complying with the robots.txt. Read the spec. - it's about not following
the listed directories, not about not listing the robots.txt.  Next
you'll want laws against bad weather and furniture with sharp corners.

Don't put things you don't want seen to see in places that can be seen.



On Mon, Dec 10, 2012 at 8:19 PM, Scott Ferguson <
scott.ferguson.it.consulting () gmail com> wrote:


    /From/: Hurgel Bumpf <l0rd_lunatic () yahoo com>
    /Date/: Mon, 10 Dec 2012 19:25:39 +0000 (GMT)


------------------------------------------------------------------------
    Hi list,


    i tried to contact google, but as they didn't answer my email,  i
do

forward this to FD.

    This "security" feature is not cleary a google vulnerability, but

exposes websites informations that are not really

    intended to be public.

    Conan the bavarian

Your point eludes me - Google is indexing something which is publicly
available. eg.:- curl http://somesite.tld/robots.txt
So it seems the solution to the "question" your raise is, um,
nonsensical.

If you don't want something exposed on your web server *don't publish
references to it*.

The solution, which should be blindingly obvious,  is don't create the
problem in the first place. Password sensitive directories (htpasswd)
-
then they don't have to be excluded from search engines (because
listing
the inaccessible in robots.txt is redundant).  You must of missed the
first day of web school.

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_______________________________________________
Full-Disclosure - We believe in it.
Charter: http://lists.grok.org.uk/full-disclosure-charter.html
Hosted and sponsored by Secunia - http://secunia.com/

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