Ensure that you are using taint checking: #!/.../perl -wT. Perl will alert you if inputed variables (tainted variables) are used in calls to your piped open or system() and die. You shouldn't be deleting various chars from the string. Do this instead: if it doesn't look like an IP address or hostname, refuse to process it. So the string should contain periods and valid upper and lowercase latin-1 chars ONLY. You can use the m// directive to determine if this is the case.

I seem to see this all too often. Input is filtered against a few regexes and assumed safe for processing. the true solution to security involves refusing input that doesn't match a criterion and that's IT. In attempt for userfriendliness, it is sometimes attempted to work around this as i see above but this can and will result in security holes that you really can't afford. So again, one filter- pass/fail.

AgentM Systems nor Nasca Enterprises nor Bone::Easy is responsible for the comments made by AgentM.

In reply to Re: CGI and Traceroute by AgentM
in thread CGI and Traceroute by Anonymous Monk

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