Google hacking is something I typically discuss when teaching ethical hacking. It’s a key component of the footprinting process. Footprinting is the blueprinting of the security profile of an organization, undertaken in a methodological manner. Footprinting is a passive process of that is designed to profile an organization with respect to networks.
The Google hacking portion of footprinting involves using advanced operators in the Google search engine to locate specific strings of text within search results. These are the same activities an ethical hacker would perform during a security assessment and are discussed in ethical hacking courses. Google hacking was pioneered by Johnny Long and focuses on the many ways to search the web for public information that may have accidently been indexed and placed on the web. A good example of these searches include common advanced operators, such as intext, filetype, intitle, inurl, link, and related. These search operators are needed because of the huge number of web sites currently on the web. It’s estimated that Google has indexed over 14 billion web pages. With so much information on the web it can be a challenge looking through it all to find specific pieces of data.
A recently released, in-house training manual from the NSA titled Untangling the Web: A Guide to Internet Research was designed to help NSA employees search for specific data and perform Google hacking techniques. This 643-page booklet details multiple ways for researchers to scourer the web when searching for specific types of information. It includes chapters on mastering the art of the search, uncovering the invisible web, Google hacking, finding people, and even footprinting web sites. While most all of this information is already publically known, it’s still interesting to see how everyone, both good guys and bad guys, use the same tools and techniques.
The book discusses some common Google search strings such as:
- intitle: “Index of” passwords modified
- allinurl:authuserfile.txt
- “access denied for user” “using password”
- “A syntax error has occurred” filetype:ihtml
The book also informs readers how to perform more advanced searches, such as spreadsheets written in Russian, that might contain usernames and passwords “filetype:xls site:ru login” or confidential spreadsheets written in German “filetype:xls site:de confidential.
Overall, Untangle the Web contains some very useful information on how to search for useful information that may not sometimes be easy to find. If you are interested in ethical hacking and the footprinting process, I would suggest you check it out.