By now, the concept of “google hacking” is pretty commonly understood.  People may not be preventing it very well, but it’s moved beyond a new thing.

For the uninitiated, though, here’s a brief summary: using Google (or any other search engine – but really, is there any other?) to find vulnerable web apps, personal information, mp3s in public directories, etc etc.  It’s great fun, and a pretty fundamental initial step of profiling an attack target.

Johnny Long was one of the main evangelists of this method and has a great database of search terms.  It’s no longer actively maintained, but you can still find plenty of good information with this as a starting point!

So Google hacking is great, but it only gets you to the public internet.  What if I wanted to profile the inside of a company, from the outside?  And passively – without hitting their servers myself?  Wouldn’t it be great if I could look for public information shared by company insiders?

Delicious seems almost perfectly designed to do this kind of activity.  For the unfamiliar, delicious is an online bookmarking site, designed around the idea that sharing bookmarks is a great way to learn about new sites.  Which is an alright idea…  but don’t people also bookmark a lot of private information?  I sure do!

Making matters worse, delicious encourages users to get started by uploading their browser bookmarks.  Essentially uploading gobs of potentially personal data to a public site.  This is a classic case of information leakage.  A dedicated attacker can use this public information to get all sorts of juicy tidbits about a company.

Let’s do some examples.  This all works great in theory, but, like Google, there is a LOT of data to sort through.  Say I’m a bad guy interested in insider information about a company.  I can start looking for the basics – say… “intranet”.  Delicious makes this easier by encouraging users to tag their posts for easy categorization:

http://delicious.com/tag/intranet

So that gives me everything that users have tagged with ‘intranet’.   Lots of sites about intranet design, usability, etc.  But also sites tagged by users to manage their own bookmarks!  So I’ll start digging into an individual company… how about AMD?

http://delicious.com/search?p=amd&u=&chk=&context=recent&tag=intranet

The first result doesn’t look interesting, but the second and third, well those sound like intranet sites!  This is confirmed by trying to follow them through and the DNS not resolving.  Nice!  Now let’s see what else this presumed AMD employee has bookmarked…

Wow, lots of development related links!  Interesting.  And what’s that link on page 2 about “AMD Manager Toolkit” ??  This fellow looks like he’s a technical manager at AMD!

Dig a little deeper, and it looks like we have another intranet site – mentioning the (presumably internal) code name of a project.  Interesting!  Go further into the links, and you see even further links to internal project Wiki pages.

Surfing around to a few of the non-intranet sites gives me an even better profile of this person.  They work with unit testing.  They use UML, C++, and Ruby, and read a lot about circuit design.  They live in India.  They’re learning guitar, and are interested in martial arts.

This may seem like innocent information to an outsider, but if I was doing this for espionage purposes, I just learned a lot about the internal operations of a project – and this is with 10 minutes of work on one webpage.  What else could I find if I dug through the internet further?

Web 2.0 is a lot of fun, and can be really useful.  But what’s often overlooked are the implications of sharing all this information.  Unless you make it a point to protect your privacy, that privacy probably doesn’t exist.  And for businesses, this can be a major potential risk.

Delicious certainly doesn’t help stop this – according to the FAQ, you cannot make your links private by default, but instead must manually edit them to make them private.  And also, the TOS leaves responsibility entirely in the hands of the users.  Very laissez-faire!

Should companies ban employees from using sites like delicious?  Probably not.  But I think that this demonstrates that employees need to be more educated on what they are exposing themselves and their employer to when using social networking sites.