security update (prototype pollution prevention) Object.freeze

lib/index.js

@@ -21,6 +21,9 @@
 // Dependencies
 // ----------------------------------------------------------------------------------
 
+Object.freeze(String.prototype);
+Object.freeze(Object.prototype);
+
 const lib_version = require('../package.json').version;
 const util = require('./util');
 const system = require('./system');

lib/internet.js

@@ -41,7 +41,7 @@ function inetChecksite(url, callback) {
           s[i] === '{' ||
           s[i] === '}')) {
           const sl = s[i].toLowerCase();
-          if (sl[0] && !sl[1]) {
+          if (sl && sl[0] && !sl[1]) {
             urlSanitized = urlSanitized + sl[0];
           }
         }