Land rapid7#1956 - fix regex error for mozilla_reduceright.rb

Author: wchen-r7

modules/exploits/windows/browser/mozilla_reduceright.rb

@@ -88,7 +88,7 @@ def junk(n=4)
 
 	def on_request_uri(cli, request)
 		agent = request.headers['User-Agent']
-		if agent !~ /Firefox\/3\.6\.[16|17]/
+		if agent !~ /Firefox\/3\.6\.(16|17)/
 			print_error("This browser is not supported: #{agent.to_s}")
 			send_not_found(cli)
 			return