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

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]

47 comments to Firesheep Makes wifi Hacking Facebook, Twitter, Google, Flickr a Breeze

  • RayR

    Hi I keep getting a Invalid interface on one system. (win7)

    And on my tablet (winXP Tablet edition) i keep getting Reference Error Cc error and nothing in the referance tab were it says websites

  • I keep getting a reference Error cc error…. Nothing happens when i try to capture something and when i go to settings i get a pop that says Reference Error Cc error.

  • Ryan

    thank you for the little tutorial but i still have a problem. my firesheep is only capturing the websites i sign into on MY computer. its not capturing other peoples computers (not even my other computer i tried to test it on!) any help would be much appreciated

    • ssstonebraker

      download wireshark and see if you can pick up traffic from other folks. if you can then firesheep should be working. let me know what happens

    • Lucy

      Not that I know a whole lot about this sort of thing, but I was wondering if the other computer that you tried it on is connected to network using a wireless router or an Ethernet connection. I haven’t seen any indication that it will not work when using computers on the same network NOT using wifi, however I have also not seen any indication that will work either. Just a thought.

  • Taylor

    i keep getting no such file or directory

    using mac

  • YarsRevenge

    I’m having the same problem as Ryan, with my Dell d610 WinXP laptop. I’ve installed wireshark and it appears to capturing traffic just fine over my wireless network (I am testing this out on my own wireless network and have my modem/router open to public unsecured at the moment, I have tried this it on open public WiFi networks with no luck as well). I’ve tried shutting my firewall down but that didn’t seem to help either. Any other ideas I can try?

  • Brent

    I’ve tried and even edited the ports and still this only pics up my lap-top not anyone else on my network. I’m wanting this to make sure no one hacks into my network so something like this working would be grateful. Any help would be great…

  • firenoob

    Ok so I just got firesheep and I’ve downloaded wincap got the cc error fixed it got the backend error and fixed it as well but when I go to interfaces I only get 2 options Realtek whick I know is my hardline and just Microsoft it dosen’t let me have the option for wifi or lan? can anyone clear this up for me please?

    • ssstonebraker

      Most wifi cards do not support promiscuous mode out of the box. To get one that does you’ll need to spend extra money for one that supports it.

      You may be able to set up packet capture on wireless using Windows bridging. I’d recommend investigating that solution if you don’t want to pay for a new adapter

      Capturing WLAN traffic on Windows depends on WinPcap and on the underlying network adapters and drivers. Unfortunately, most drivers/adapters support neither monitor mode, nor seeing 802.11 headers when capturing, nor capturing non-data frames.

      Promiscuous mode can be set; unfortunately, it’s often crippled. In this mode many drivers don’t supply packets at all, or don’t supply packets sent by the host.

      If you experience any problems capturing packets on WLANs, try to switch promiscuous mode off. In this case you will have to capture traffic on the host you’re interested in.

  • firenoob

    and also it dosen’t capture the sites even on my machine when testing so if some one could help? I’m just staring at the stop capturing button so I know it’s working just now correctly thnx sorry for the double post.

  • hkid

    Yea, I downloaded firesheep and when I hit start capturing nothing happens. Then when I hit stop capturing a message says ignoring duplicate header: cache-control, Old:max-age=0,New:no-cache. How do I fix this?

  • Yea i downloaded firesheep and got it ready. When I started capturing nothing happen and then I hit stop capturing I got the following message.Ignoring duplicate header:cache-control,Old:max-age=0,New:no-cache,Ignoring duplicate header:cache-control,Old:max-age=0,New:max-stale=0. Ignoring duplicate header:cache-control,Old:max-age=0,New:min-fresh=1000, so how do I fix this? thanks

  • mmemo

    what should i put in advanced filter

  • Jon

    Im using windows 7. Downloaded firefox 3.6.18 and latest winpcap. The firesheep doesn’t detect any sites when capturing starts. Did the same procedure with my mac and works ok. So is firesheep just not compatible for win 7?

  • Nuno

    I’m trying it on Windows 7 64 bits, Firefox 3.6.19 (as it didn’t work with Firefox 5).

    When I start downloading, it doesn’t pick anything (even from the local machine), and when I stop it, it gives a “Backend exited with error 1”.

    I’m sniffing the local wired network, and I see with wireshark packets are arriving.

    Is there something wrong with my setup, or am I missing something?

    Thank you,

  • Bob

    I’ve installed firesheep and downloaded WinPcap yet I still can’t capture anything I have two people in my house logged into facebook and it wont recognize them

  • guys PLEASE HELP for me it says
    ‘fire fox could not install the file
    because: unexpected installation error review the error console log for more information! GUYS PLEASE HELP ME I BEG YOU!how i can fix ttat?

  • dalibor

    i cant get facebook cookies pleasec help 🙂 it works finw with other accounts

  • Michael

    Ok so when i try to open up the file with firefox it just opens it like 1000 times i have deleted it and redownloaded it and idk what wrong. i have also tryied to open it with many different versions of firefox

  • Michael

    So i downloaded the file and i have the correct version of firefox. but whenever i open the file with fire fox all it does is make a ton of windows saying the file name. idk what to do i have followed the apporpiate instructions and it wont work for me.

  • ABHI

    this work only for wifi
    me use ethernet and want to catch cookies other account…???

  • Mamba

    this is really rad …
    seems like no one in the net is having a solution for this problem .
    Seems like user of old macbook pros ( no unibody) are having problems capturing data with firesheep from others in the network.
    For me the same. I can see my accounts , but not the other ones. Installed wireshark and used it in promicous mode and monitor mode and
    it is capturing the network data! , seems like it there is a code problem inside firesheep unable to put the airport into promicous mode for
    using it right, ( seems like newer mbp modells are using 802.11 n and older are using mbp are using 802.11 a/b/g ).. or pcap code is not working right …

    Perhaps i am completly wrong … dont know …
    anybody got a solution?

  • ishwar

    i downloaded firesheep …. but was unable to detect any website … i am using a wifi connection at home where i am not able to detect any website which that i log in from my laptop as well as other laptops using the same wifi connection .

  • I could not download firesheep…it turned into a zip file…how do I change it back to xpi?

  • toonbreak

    Hi – please help!
    I’ve downloaded and installed Firesheep om my mac running Osx v10.6.8. My Firefox is v3.6.23. I can see the sidebar and I’ve clicked “start capturing” i’ve also checked the correct interface is selected in the prefs. I get no results unless i log in to a site on this computer. I’ve been trying to test it on my pc laptop running Windows Vista but cant pick anything up. I’m not that techy so responses in simlpe novice language would be most appreciated! Thanks 🙂

  • i'm thai

    it not enloy’


  • waky Isha

    I’m using FireFox ver 3.6 on Mac Lion and the installation process went fine. When I start capture nothing happens. I used Winshark and can successfully capture all the data. Any ideas..

    In the Preference section for FreeSheep I selected Facebook and then it asked me name it. Is this correct. Do you have select the appropriate Apps to capture?



  • Hey there just a question I am running firesheep and winpcap as well but when I am starting it everything is fine ( but I am not getting anything even from my own pc) when i click stop an msg like backend exited with error1. I have not changed any of the options I mean the preferences what should I do ? I am running it on firefox 3.6.17! Please help!

  • firesheep2121

    My mac im running firesheep on firefox and i clicked started capturing and then i opened google chrome and nothing came up when i logged into facebook? please answer me?

  • komal

    i am using windows n i’ve installd winpcap n firesheep too. Howevr, when i click capture, “failed to set hardware filter to promiscuous mode” msg appears on the screen. What should i do. please help

  • fabian

    I installed WinPacp and then Firesheep if i stop capturing i got the error 1 “Backend exited with error 1”. And it dosent record the information/Passwords. Need Help

  • XP

    Hi , how are you .. i downloaded the firesheep and when i press Start Capturing ” Backend exited with error 1. ” you said ignore this error . but actually i am still trying but it doesn’t work .. i am working on my wifi at home and i really need this firesheep .. please help me

    • ssstonebraker

      Most vendors have patched the flaw exposed in firesheep. You’ll need to write your own rules for firesheep and your wireless adapter may not be able to sniff the packets, try an ethernet connection

  • everything seems to be okay but i wont capture anything? should i change the preference bar to the ethernet, microsoft, or interface driver? or is it the fliter that i need to change? i have a windows vista… someone please help.

  • hey thanks for all this realllllllllllllllliiiiiiiiiiiii useful information thhanks soo much but i got a problem ……. one of my friends sit in the next room with facebook opened and yet when i hit start caturing nothing appears…why is that??? why nothing appears??? and also when i hit stop capturing THE BACKENED EXITED WITH ERROR 1 appers…..well pleaaaaaaaaaaaseeeeeeeeeee solve this problem i wanna get it s solution immediately plxxxxxx

  • Ricky

    Anyone find the solution to this problem yet? I followed everyone’s advice and still nothing shows up when I start capturing?? Can someone please help me

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.