I was wondering if there are any security concerns in my .pl file?

Yes - as LanX already alluded to, this is susceptible to a Cross Site Scripting (XSS) attack. One way to help mitigate this is to escape any strings you're inserting into the HTML, for example with HTML::Entities. Other comments:

• Always Use strict and warnings!
• The whole @pairs code seems unneccessary, it looks like you've copied some really old Perl form parsing code from somewhere, but this is not needed because you're already using CGI.pm which does this for you.
• You're not checking open for errors - "open" Best Practices
• You're not locking your drivers.html file while you are editing it, which could cause problems when multiple requests are submitted at the same time (though I don't know how flock behaves on Windows).

But really, you shouldn't be using this really old-school CGI.pm style code anymore. You probably want to look into UP-TO-DATE Comparison of CGI Alternatives, in particular I'm a fan of Mojolicious, its templating engine would be very useful here because it can escape HTML special characters automatically when inserting variables into HTML. I have a bunch of Mojo examples on my scratchpad Update: and I've now posted a full example here.