Full Disclosure mailing list archives
Re: defense against session hijacking
From: "Jason Ziemba" <jason () ziemba net>
Date: Tue, 18 Nov 2003 08:18:55 -0500 (EST)
I'm not going to claim that my method is fool-proof, but.. If you are using sessions on your site then you should have the ability to track the movement of a user through-out your system. If you record the last page the user was on (with a specific session-id) and then check the referrer server variable on their next hit. Compare the referrer to their last known page. Most of the time (depending on the complexity of your site) the referrer and last known page should match. If their session is 'hijacked', odds are the 'hijacker' will not be following in a valid user's footsteps, more likely they will just be coming at the server with rogue data. The referrer check won't match and thus the validity of the session request is also void. The catch is, how much programming are you willing to do to ensure the integrity of your system. If you are looking for the easy-route (using PHP's embedded session module) then there is no direct way to secure the sessions. If you are willing to build you own session module for your given CGI language then the sky is the limit (as long as you are willing to get your hands dirty at the start). Jason Ziemba
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hi All, Sorry if this is common knowledge or regularly discussed; I'm fairly new to the list. I see quite a few messages on this and other security lists about session hijacking in Web applications. Isn't it good defense for a programmer to store the IP address of the client when the session is initiated, and then compare that address against the client for each subsequent request, destroying the session if the address changes? Do many programmers really overlook this simple method to protect against such an attack? It's not perfect but should significantly increase the difficulty of such an attack with little or no annoying side effects for the legitimate user. Would it be useful to extend the session modules of the common Web scripting languages (e.g. PHP) to enable an IP address check by default? Best Regards, - -- :: t h o m a s d u f f e y :: h o m e b o y z i n t e r a c t i v e -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.2 (GNU/Linux) Comment: Using GnuPG with Thunderbird - http://enigmail.mozdev.org iD8DBQE/uTrH8fKWAp8CzDARAhyOAJ9kXkkiUERgEVRWhH5GtGACTKA1hwCfak+7 KsyUSQG+iAcPVxX3BIdTTRc= =9f2R -----END PGP SIGNATURE----- _______________________________________________ Full-Disclosure - We believe in it. Charter: http://lists.netsys.com/full-disclosure-charter.html
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Current thread:
- Re: defense against session hijacking, (continued)
- Re: defense against session hijacking Ron DuFresne (Nov 19)
- Re: defense against session hijacking David Maynor (Nov 17)
- Re: defense against session hijacking Damian Gerow (Nov 17)
- Re: defense against session hijacking Frank Knobbe (Nov 17)
- Re: defense against session hijacking Damian Gerow (Nov 17)
- Re: defense against session hijacking David Maynor (Nov 17)
- Re: defense against session hijacking Damian Gerow (Nov 17)
- window hiding sir kaber (Nov 17)
- Re: defense against session hijacking |reduced|minus|none| (Nov 17)
- Re: defense against session hijacking Scott Taylor (Nov 17)
- Re: defense against session hijacking Bill Pennington (Nov 17)
- Re: defense against session hijacking Jason Ziemba (Nov 18)
- Re: defense against session hijacking Tim (Nov 18)
- Re: defense against session hijacking Jakob Lell (Nov 19)
- Message not available
- Re: defense against session hijacking flatline (Nov 19)