"Accept Known Good" and potential attacks
Posted: Thu Mar 18, 2010 3:16 pm
I've just recently been introduced to the concept of "Accept Known Good" via the OWASP document:
http://www.owasp.org/index.php/Data_Val ... known_good
...with the idea of instead of rejecting badly formed input, a whitelist of acceptable inputs can be used to validate against. I understand the basics, love the idea, but I am curious as to what the consensus is in regards to what attacks could still thwart AKG if the code is written such that no user input is ever trusted and the only values passed on to the scripts are the allowable ones from the whitelist?
Hope someone with more insight can elaborate. Be warned - I'm also not a security person, so I may have more questions as this discussion continues.
Thanks!
http://www.owasp.org/index.php/Data_Val ... known_good
...with the idea of instead of rejecting badly formed input, a whitelist of acceptable inputs can be used to validate against. I understand the basics, love the idea, but I am curious as to what the consensus is in regards to what attacks could still thwart AKG if the code is written such that no user input is ever trusted and the only values passed on to the scripts are the allowable ones from the whitelist?
Hope someone with more insight can elaborate. Be warned - I'm also not a security person, so I may have more questions as this discussion continues.
Thanks!