Fix malicious/bad JS exploits

code/modules/client/client defines.dm

@@ -36,6 +36,7 @@
 		//SECURITY//
 		////////////
 	var/next_allowed_topic_time = 10
+	var/info_sent = 0
 	// comment out the line below when debugging locally to enable the options & messages menu
 	//control_freak = 1
 

code/modules/client/client procs.dm

@@ -25,7 +25,12 @@
 		return
 
 	if (href_list["EMERG"] && href_list["EMERG"] == "action")
-		handle_connection_info(src, href_list["data"])
+		if (!info_sent)
+			handle_connection_info(src, href_list["data"])
+			info_sent = 1
+		else
+			server_greeting.close_window(src, "Your greeting window has malfunctioned and has been shut down.")
+
 		return
 
 	//Reduces spamming of links by dropping calls that happen during the delay period