A better would be to look through the string they send you and check for potentially harmful substitutions

Better than that is to filter everything except known-good characters, like we do when untainting data. In fact, the OP program should run under taint mode.

--
David Serrano

In reply to Re^4: How to do regex backreferences within $variable replacement text? by Hue-Bond
in thread How to do regex backreferences within $variable replacement text? by ManFromNeptune

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