There are some personal information on Facebook that you just cannot completely hide — Your friends list are among those, even if there is an option to hide it.
The issue resides in the Facebook's mutual-friends feature concept, which has been in controversies in the past, raising privacy concerns.
But now, a new Free Chrome extension called "Facebook Friends Mapper" (developed by Alon Kollmann) can expose a lot more than just mutual friends of the two Facebook users in "just one click," creating high security and Privacy risks for Facebook users.
Generally, Facebook also allows you to set the visibility of your list of Facebook friends to "Only Me" if you want to keep your friends list hidden from other Facebook users as well as your own friends.
However, the problem is…
...even if you set your friends list to private, other Facebook users may still be able to see part of your hidden Friends list and that part is a lot more than just your mutual friends.
How does Facebook Friends Mapper Chrome extension work?
Facebook Friends Mapper extension leverages the Mutual Friends feature of the social networking site to crawl and expose your hidden Facebook Friends list.
If, for example, Facebook CEO Mark Zuckerberg does not share his friends list with the public and neither I am on his friend list. However, I have at least one mutual friend with him. Therefore…
...using Facebook Friends Mapper tool I would be able to see most of his hidden Facebook friends by exploiting the 'mutual friend' logical flaw.
How to use Facebook Friends Mapper Chrome extension?
1. Install Facebook Friends Mapper extension from Chrome web store.
3. You will find 'Reveal Friends' option on Friends tab.
Just one condition to meet:
In case you want to see hidden Facebook Friend list of anyone, you can use Facebook Friends Mapper extension if you fulfill the following conditions:
Facebook user, whose friends list you want to target, must have at least one mutual friend with you, and doesn't matter if you are friends with him/her or not.
Facebook Friends Mapper Chrome extension launched just a few days ago, so most of the users are yet unaware about this Facebook Hacking Tool.
You can Install Facebook Friends Mapper Chrome extension from free from Google Chrome Extension Store.
If you are willing to keep your friend list private, then please note that Facebook's current privacy setting would not help you to resolve the issue. So, we expect a privacy patch from Facebook Security team as soon as possible before this tool goes wild.