Re: Session security with cookies

Hi,

Jeffory Atkinson wrote:
> Till,
> Here are some factors that you will want to ensure.
> -Session token is delivered after authentication
> -Each session token is unique and not predictable (requiring a strong
> random token generator)
> -Session token is transfer over an encrypted tunnel
> -Session token is marked secure
> -Ensure the session is terminated at logout
> -Ensure the session times out in a reasonable amount of time
> -All access control should be based on the user's session token and only
> the session token

The information to authenticate a user should not rely solely on the
session cookie. In this case it would be vulnerable to CSRF (Cross
Site Request Forgery) attacks. It's necessary to use another token
(URL parameter, hidden form fields, etc.) cryptographically secure
to prevent these attacks.

Regards,

-- 
_________________________________
Vicente Aguilera Díaz
Director Auditoría
CISA, CISSP, ITIL, CEH Instructor, OPSA, OPST
OWASP Spain Chapter Leader
vaguilera_at_isecauditors.com
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www.isecauditors.com
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> 
> -----Original Message-----
> From: listbounce_at_securityfocus.com [mailto:listbounce_at_securityfocus.com]
> On Behalf Of Till Elsner
> Sent: Monday, December 03, 2007 6:32 PM
> To: webappsec_at_securityfocus.com
> Subject: Session security with cookies
> 
> Hi, i'm investigating in web application security this time and i'm  
> trying to find some information about session management with cookies  
> and related security issues. Can anyone point me to tips on how to  
> make cookie based sessions more secure and how to prevent session  
> hijacking? How secure is session handling using cookies and what are  
> the main risks? Is anyone aware of good literature on that topic?
> Thanks and have a nice day
> Till
> 
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