A variable can only be untainted by extracting

Variables aren't tainted. Scalar values are tainted. Thus, portions of a hash can be tainted while other parts aren't. (Or an array.)

Once a variable is tainted, Perl won't allow you to use it in a system(), exec(),

Second nit, I haven't tested this but according to Perlsec, you can use the LIST form of system and exec and taint-checking is bypassed.

In reply to Small nit, RE: RFC - CGI Course by clintp
in thread Request for Comments - CGI Course by Ovid

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