For some reason I’m not allowed to respond to the child comment so I’m putting this here:

Perl 5 was released in 1994. Palo Alto Networks was founded in 2005, so Perl 5 was certainly available when they built their first products and would have been a superior choice to either PHP or Perl 4.

You win.

Perl 4 specifically of course though.

That's for mission-critical load-bearing infrastructure hidden behind modernized interfaces. Nobody has touched that script in 33 years.