Full Disclosure mailing list archives
Re: Google's robots.txt handling
From: Stefan Edwards <saedwards.ecc () gmail com>
Date: Mon, 10 Dec 2012 15:28:53 -0500
On Mon, Dec 10, 2012 at 3:21 PM, James Lay <jlay () slave-tothe-box net> wrote:
On 2012-12-10 12:25, Hurgel Bumpf wrote: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. (Additionally i have to say that i advocate robots.txt files without sensitive content and working security mechanisms.) Here is an example: An admin has a public webservice running with folders containing sensitive informations. Enter these folders in his robots.txt and "protect" them from the indexing process of spiders. As he doesn't want the /admin/ gui to appear in the search results he also puts his /admin in the robots text and finaly makes a backup to the folder /backup. Nevertheless these folders arent browsable but they might contain f(a)iles with easy to guess namestructures, non-encrypted authentications (simple AUTH) , you name it... Without a robots.txt nobody would know about the existance of these folders, but as some folders might be linked somewhere, these folders might appear in search results when not defined in the robots.txt The admin finds himself in a catch-22 situation where he seems to prefer the robots.txt file. Long story short. Although google accepts and respects the directives of the robots.txt file, google INDEXES these files. This my concern.http://www.google.com/search?q=inurl:robots.txt+filetype%3Atxt+Disallow%3A+%2Fadminhttp://www.google.com/search?q=inurl:robots.txt+filetype%3Atxt+Disallow%3A+%2Fbackuphttp://www.google.com/search?q=inurl:robots.txt+filetype%3Atxt+Disallow%3A+%2FpasswordAs these searches can be used less for targeted attacks, they more can be used to find victims.http://www.google.com/search?q=inurl:robots.txt+filetype%3Atxt+%2FDisallow%3A+wp-adminhttp://www.google.com/search?q=inurl:robots.txt+filetype%3Atxt+%2FDisallow%3A+typo3<Just be creative> This shouldn't be a discussion about bad practice but the google feature itself. Indexing a file which is used to prevent indexing.. isn't that just paradox and hypocrite? Thanks, Conan the bavarianI'm wondering if, in perhaps .htaccess, one could allow ONLY site crawlers access to the robots.txt file. Then add robots.txt to robots.txt...would this mitigate some of the risk? James
You'd probably end up accidentally block bots though if you did it via ip range, and you wouldn't be safer at all if you did it by UserAgent string. I think it'd be safer to just assume robots.txt is going to be looked at by someone other than actual robots.
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Current thread:
- Google's robots.txt handling Hurgel Bumpf (Dec 10)
- Re: Google's robots.txt handling James Lay (Dec 10)
- Re: Google's robots.txt handling Gynvael Coldwind (Dec 10)
- Re: Google's robots.txt handling Benji (Dec 11)
- Re: Google's robots.txt handling Swair Mehta (Dec 11)
- Re: Google's robots.txt handling Stefan Edwards (Dec 11)
- Re: Google's robots.txt handling Gildseth, Tommy (Dec 11)
- Re: Google's robots.txt handling Gynvael Coldwind (Dec 10)
- Re: Google's robots.txt handling Philip Whitehouse (Dec 11)
- Re: Google's robots.txt handling Denis McMahon (Dec 11)
- Re: Google's robots.txt handling Lehman, Jim (Dec 12)
- Re: Google's robots.txt handling Christoph Gruber (Dec 12)
- Re: Google's robots.txt handling Patrick Webster (Dec 12)
- Re: Google's robots.txt handling Mario Vilas (Dec 13)
- Re: Google's robots.txt handling Philip Whitehouse (Dec 13)
- Re: Google's robots.txt handling Jeffrey Walton (Dec 13)
- Re: Google's robots.txt handling Julius Kivimäki (Dec 14)
- Re: Google's robots.txt handling Christoph Gruber (Dec 12)
- Re: Google's robots.txt handling James Lay (Dec 10)