The security issue is "not validating user input" (under certain circumstances) and not "making a string into a subroutine call". If the subroutine cannot be resolved, perl will complain (i.e. die), and done. So "validating user input" doesn't apply in the OP's context.

It is just what your shell is doing, day in, day out.

--shmem 

_($_=" "x(1<<5)."?\n".q·/)Oo.  G°\        /
                              /\_¯/(q    /
----------------------------  \__(m.====·.(_("always off the crowd"))."·
");sub _{s./.($e="'Itrs `mnsgdq Gdbj O`qkdq")=~y/"-y/#-z/;$e.e && print}

In reply to Re^4: variable subroutine call by shmem
in thread variable subroutine call by davg

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