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Open Redirection-How to Secure it

When the OWASP has also included this issue in it's Top Ten 2010 list and also I have been finding lots of unvalidated redirects in the applications assessed everyday, I was just giving standard recommendation to developers to go for whitelisting approach. Include a set of valid domains- to which only your users should be forwarded- into your application. Once you have identified a “whitelist” of trusted domains, put the list in a configuration file on the server or database. From a secure coding perspective, the redirection servlet or script should not take a URL as a parameter. Instead, require that the servlet accepts an index that maps to the list of trusted domains.
But as I am not very good in coding I was not able to assist them in coding.
Eventually today I stumbled upon a very nice article here. It describes the best practices for redirecting users to trusted domains and how to 'code' that.
Please visit: http://mikeware.us/goodcode/?p=260

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