Firesheep Makes wifi Hacking Facebook, Twitter, Google, Flickr a Breeze

October 26, 2010

Firesheep Quickstart – windows xp:

  • Click here to download firesheep-0.1-1.xpi straight from github..
  • Install latest version of winpcap
  • Update your Firefox to at least 3.6.12


Q: How do i fix Couldn’t open device x: Error opening adapter: the system cannot find the device specified?

A: Select a different interface and restart firefox (see screenshot below)

Q: Why isn’t anything happening?
A: If no one else is logging in to facebook, yahoo, gmail, twitter, etc on your network with saved off information you won’t see anything, be patient!

Q: What does ” backend exited with error 1 ” mean?

A: It doesn’t matter, the developer said that this is normal and had an issue when trying to remove it before he released the code.  So please just act like it isn’t there!

Firesheep was just announced by Eric Butler at Toorcon 12.  This firefox addon steals cookies (containing authentication information for websites) sent via HTTP over public wifi, allowing you to pwn unsuspecting wifi users facebook, gmail, twitter, flickr, youtube, etc accounts.

What is so groundbreaking about this particular add-on is that it has essentially brought one-click hacking to the masses (like napster, bittorrent did with piracy).  It will be interesting to see how fast these big sites path up their lazy ways.  Until then ensure you always delete all your cookies before browsing the web on public wifi!

After installing the extension you’ll see a new sidebar (Browser Requirements: Firefox >= 3.6.10.  You must enable the sidebar in View/Sidebar/Firesheep, on windows install winpcap)

. Connect to any busy open wifi network and click the big “Start Capturing” button. Then wait.

As soon as anyone on the network visits an insecure website known to Firesheep, their name and photo will be displayed:

Double-click on someone, and you’re instantly logged in as them.

That’s it.

Download firesheep
Help installing

For Mac people receiving the –fix-permissions error, here’s what to do:
1) Under Applications -> Utilities open Terminal
2) Copy-and-Paste this into Terminal:

sudo “~/Library/Application\ Support/Firefox/Profiles/*/extensions/firesheep\” –fix-permissions

[that should all be on one line, no matter how it appears on this webpage]

3) It will ask you for your password, type it in.
4) Restart firefox and the error should go away

If you have FileVault enabled, it will mount your home directory as “nosuid”, so the packet-capturing backend won’t be able to run until you Copy-and-Paste these additional commands into the Terminal to move the firesheep-backend to a place it can run SUID root:

sudo mv “~/Library/Application\ Support/Firefox/Profiles/*/extensions/firesheep\” /usr/bin/firesheep-backend

sudo ln /usr/bin/firesheep-backend “~/Library/Application\ Support/Firefox/Profiles/*/extensions/firesheep\”

[again, each command should all be on one line, no matter how it appears on this webpage]