Your better strategy is to avoid exposure by never feeding user input to the shell. If you must give arguments to utilities, use the list form of system, magic open, or exec so that no shell interpretation of the command line is done.

You'd need an accurate combination html/shell parser to sanitize shell constructs from html fragments. Why bother, if the text never gets shell-interpreted? Your users might discuss shell programming without any ill intent.

After Compline,
Zaxo

In reply to Re: Remove or Identify Shell Commands In A Form by Zaxo
in thread Remove or Identify Shell Commands In A Form by rongoral

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