Why do you want to do this via a CGI interface?

You could write a wrapper in C which execs your script and setuid the wrapper. Better might be to have the script call a setuid program that does the minimal amount necessary with root privs. Whatever you do, be extremely careful with user input. Run with tainting enabled (-T) and untaint the data very carefully.

Better yet, just don't do this.

-sauoq
"My two cents aren't worth a dime.";