I would suggest adding more validation of the expected inputs and removing unexpected inputs.

You might still consider trying to use taint. Seeing what breaks could help you find some of the vulnerabilities in the program.

Also, there is the tainted function which you can use yourself. Any place in the code where potentially malicious data could be a problem, the tainted function can be used to help detect unsanitized input.

However, it would really be better to add more validation to the programming so that all of the inputs are either properly validated or removed.

If all else fails, you could "wrap" the program with a "sanitizing proxy" that cleans up the inputs then forwards the cleaned CGI request to your legacy CGI.

In reply to Re: Taint tracing a single variable? by RonW
in thread Taint tracing a single variable? by PFudd

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