[Full-disclosure] Re: Session data pollution vulnerabilities inweb applications

[Dave Korn]

Frank Knobbe wrote in news:1137084647.25372.13.camel at localhost
>These type of bugs stem from bad program design. (BTW: I wouldn't call
>it session data pollution... your not polluting anything).

  Yes he is.  He's polluting sanitized data with tainted data.  It's a 
fairly reasonable description if you ask me.

> The proposed fix is -- besides being only specific to this example --
>equally flawed. The underlying issue is that you trust user supplied
>data.

  NO!  You've /completely/ failed to understand the post.

  The underlying issue is not that the user-supplied data is trusted, 
because it isn't, it gets validated.  The _underlying_ issue is that the 
*same* location is used to store both trusted and non-trusted data, and 
there's no way for the application to know which kind of data was last 
stored in that location.

    cheers,
      DaveK
-- 
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