Not a PHP dev, but it seems calling `extract` is itself potentially insecure. The php docs warn against it (https://www.php.net/manual/en/function.extract.php):

> Do not use extract() on untrusted data, like user input (e.g. $_GET, $_FILES). If you do, make sure you use one of the non-overwriting flags values such as EXTR_SKIP and be aware that you should extract in the same order that's defined in variables_order within the php.ini.

Looks like calling it can shadow previously defined, unrelated variables?

Edit: On re-reading your comment, yes, if $requiredHeaders is previously sanitized then the code is technically safe. But it still presents as an insecure coding practice.