Most popular web services that you visit today require you to login using a username and password. If authenticated, the server saves a cookie on the user’s computer which will be sent along with every subsequent request. This cookie acts as an authentication token that tells the server that the request maker has full access to the current account.
HTTP hijacking, or otherwise known as sidejacking, occurs when an attacker captures a user’s cookies and is able to login as said user with all privileges and accesses intact.
When using an open wireless network, your network traffic is available for everyone to see. This includes cookies. Thus, it’s almost trivially easy for an attacker to steal your cookie on an open wireless network and perform a sidejacking attack.
The only real defense from sidejacking is to force ssl end to end encryption from the moment the user connects to the server. The downside is that this makes each and every network request more expensive and was enforced by very few of the major service providers.
While sidejacking vulnerabilities have always been a major security flaw in open wireles
networks, it didn’t receive much public attention until in 2010 when developer Eric Butler published an infamous firefox app known as firesheep.
Firesheep automated sidejacking attacks. If connected to an open wireless network, it would automatically capture any cookies sent through the air. It also contained a list of configurations for popular web services like facebook and google. When a cookie of a corresponding service was detected, the users name and picture would be displayed on the sidebar. Clicking on the name would take you to the users account.
After the release of firesheep, major websites like google and facebook enforced SSL only connections and enabled the secure attribute on their authentication cookies that mandated these cookies could only be sent over https.
I was curious to see that now, over two years after firesheep, exactly was the state of sidejacking protection is in major web services. Many of my friends use Rice Visitors as their default form of wireless without batting an eye. Even among my more tech inclined friends who knew the dangers of using open wireless, they wasn’t much alarm at using
open wireless. Were they safe?
I examine the top 10 sites on the web as according to their ranking on Alexa.
1. Google:
Https only. In addition, copying cookies verbatim didn’t lend to successful sidejacking attack.
I logged in to the same gmail account on a different browser and found that there were two cookies with different values in my two gmail sessions.
GX
GMAIL_AT
These cookies both had a random seeming alphanumeric value. Deleting GMAIL_AT didn’t seem to affect anything but deleting GX logged me out of my account. My guess is that GX is some sort of distinct session based value that google uses to thwart sidejacking attempts.
2. Facebook:
Https only. Authentication cookies (c_user) are https only.
Visiting the website using http reveals the locale of the user via non secure cookies. The attacker, if accessing the same wireless network as the victim, should already have access to this information so it doesn’t seem to be much of a vulnerability.
3. Youtube:
Http access only. Confirmed sidejacking. I suppose that adding the extra latency of SSL on top of the world’s largest online streaming video site is not something google decides is feasible at the moment.
4. Yahoo:
Http access only. Confirmed sidejacking.
5. Baidu:
Http access only. Confirmed sidejacking.
6. Wikipedia:
Http access. Optional https available. Confirmed sidejacking.
7. Windows Live:
Https only. Got this warning when logging in via Http.
“””
As long as you’re just reading and writing email, signing in with “https” gives you extra security. But this extra security disappears if you check your calendar, edit a contact, or go to another site.For the most secure connection, we strongly recommend that you change your settings to always use HTTPS.
“””
In addition, it doesn’t seem that the cookies in live have the “secure” setting set to true. That means if a user is logged in and visits live.com over HTTP, their cookies will still be sent over the clear before being redirected to HTTPS.
8. Amazon
Http access only . Confirmed sidejacking.
At first this seems like a glaring security hole. Amazon is the world’s largest online retailer and as of 2011, was processing $17.43 billion worth of items annually (source: http://phx.corporate-ir.net/phoe…).
Amazon asks for user password when
asks you for confirmation before making a purchase. Confirmation is also
necessary to do anything privacy related, whether it’ll be changing
account information or looking at past orders. j
9. QQ
Http access only. Confirmed sidejacking.
10. Twitter
Https only. Authentication cookies (auth_token) are https only.