Testing: Spidering and googling

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Brief Summary
This section describes how to retrieve information about the application being tested using spidering and googling techniques.

Description of the Issue
Web spiders are the most powerful and useful tools developed for both good and bad intentions on the Internet. A spider serves one major function, Data Mining. The way a typical spider (like Google) works is by crawling a website one page at a time, gathering and storing the relevant information such as email address, meta-tags, hidden form data, URL information, links, etc. The spider then crawls all the links in that page, collecting relevant information in each following page, and so on. Before you know it, the spider has crawled thousands of links and pages gathering bits of information and storing into a database. This web of paths is where the term 'spider' is derived from.

The Google search engine found at http://www.google.com offers many features, including language and document translation; web, image, newsgroups, catalog, and news searches; and more. These features offer obvious benefits to even the most uninitiated web surfer, but these same features offer far more nefarious possibilities to the most malicious Internet users, including hackers, computer criminals, identity thieves, and even terrorists. This article outlines the more harmful applications of the Google search engine, techniques that have collectively been termed "Google Hacking." In 1992, there were about 15,000 websites, in 2006 the number has exceeded 100 million. What if a simple query to a search engine like Google such as "Hackable Websites w/ Credit Card Information" produced a list of websites that contained customer credit card data of thousands of customers per company? If the attacker was aware of a web application that utilized a clear text password file in a directory and wanted to gather these targets, he could search on "intitle:"Index of" .mysql_history" and found on any of the 100 million websites the engine will provide you with a list of the database usernames and passwords. Or prehaps the attacker has a new method to attack a Lotus Notes web server and simply wants to see how many targets are on the Internet, he could search "inurl:domcfg.nsf". Apply the same logic to a worm looking for its new victim.

Spidering
Description and goal

Our goal is to create a map of the application with all the points of access (gates) to the application. This will be useful for the second active phase of pen testing. You can use tool such as wget (powerful and very easy to use) to retrieve all the information published by the application.

Test:

The -s option is used to collect the HTTP header of the web requests.

wget -s

Result:

HTTP/1.1 200 OK Date: Tue, 12 Dec 2006 20:46:39 GMT Server: Apache/1.3.37 (Unix) mod_jk/1.2.8 mod_deflate/1.0.21 PHP/5.1.6 mod_auth_ passthrough/1.8 mod_log_bytes/1.2 mod_bwlimited/1.4 FrontPage/5.0.2.26 34a mod_ssl/2.8.28 OpenSSL/0.9.7a X-Powered-By: PHP/5.1.6 Set-Cookie: PHPSESSID=b7f5c903f8fdc254ccda8dc33651061f; expires=Friday, 05-Jan-0 7 00:19:59 GMT; path=/ Expires: Sun, 19 Nov 1978 05:00:00 GMT Last-Modified: Tue, 12 Dec 2006 20:46:39 GMT Cache-Control: no-store, no-cache, must-revalidate Cache-Control: post-check=0, pre-check=0 Pragma: no-cache Connection: close Content-Type: text/html; charset=utf-8

Test:

The -r option is used to collect recursively the web-site's content and the -D option restricts the request only for the specified domain.

wget -r -D

Result:

22:13:55 (15.73 KB/s) - `www.******.org/indice/13' saved [8379]

--22:13:55-- http://www.******.org/*****/******** => `www.******.org/*****/********' Connecting to www.******.org[xx.xxx.xxx.xx]:80... connected. HTTP request sent, awaiting response... 200 OK Length: unspecified [text/html]

[  <=>                                                                                                                                                                ] 11,308        17.72K/s

...

Googling
Description and goal

The scope of this activity is to find the information about a single web-site published on the internet or to find a specific kind of application as Webmin or VNC. There are many tools that carry out these specific queries as googlegath but it is possibile to perform this operation also using directly Google's search on the web-site. This operation doesn't require an high technical skill and is a good way to collect information about a web target.

 Tip cases of Advance Search with Google 


 * Use the plus sign (+) to force a search for an overly common word. Use the minus sign (-) to exclude a term from a search. No spaces follow these signs.
 * To search for a phrase, supply the phrase surrounded by double quotes (" ").
 * A period (.) serves as a single-character wildcard.
 * An asterisk (*) represents any word —- not the completion of a word, as is traditionally used.

Google advanced operators help refine searches. Advanced operators use the following syntax: operator:search_term. Notice that there is no space between the operator, the colon, and the search term. A list of operators and search terms follows:
 * The site operator instructs Google to restrict a search to a specific web site or domain. The web site to search must be supplied after the colon.
 * The filetype operator instructs Google to search only within the text of a particular type of file. The file type to search must be supplied after the colon. Don't include a period before the file extension.
 * The link operator instructs Google to search within hyperlinks for a search term.
 * The cache operator displays the version of a web page as it appeared when Google crawled the site. The URL of the site must be supplied after the colon.
 * The intitle operator instructs Google to search for a term within the title of a document.
 * The inurl operator instructs Google to search only within the URL (web address) of a document. The search term must follow the colon.

The following are a set googling examples (for a complete list look at [1]):

Test:

site:www.xxxxx.ca AND intitle:"index.of" "backup"

Result:

The operator :site restricts a search in a specific domain, while the :intitle operator makes it possibile to find the pages that contain "index of backup" as a link title of the Google output. The AND boolean operator is used to combine more conditions in a same query.

Index of /backup/

Name                   Last modified       Size  Description

Parent Directory       21-Jul-2004 17:48      -

Test:

"Login to Webmin" inurl:10000

Result:

The query produces an output with every Webmin authentication interface collected by Google during the spidering process.

Test:

site:www.xxxx.org AND filetype:wsdl wsdl

Result:

The filetype operator is used to find specific kind of files on the web-site.