Comment: rakwrite/rakfail vulnerability info

--- 20.md
+++ 19.md
@@ -1,3 +1,8 @@
+# Security Warning!
+It's been discovered that clients ranging from 2012 to 2018 have an unpatched [denial-of-service](https://en.wikipedia.org/wiki/Denial-of-service_attack) vulnerability.
+It's recommended that you patch your client & server using the below site to make sure you are safe before hosting.
+[https://my-thos.github.io/rakwrite/patcher](https://my-thos.github.io/rakwrite/patcher)
+
 # If you *can* port forward...
 You can find a general video guide to how to port forward [here](https://www.youtube.com/watch?v=jfSLxs40sIw), and a wikihow article [here](https://www.wikihow.com/Set-Up-Port-Forwarding-on-a-Router).
 1. When hosting ROBLOX servers, the internal port is usually set to 53640. This is not necessarily the only port you can port forward to, but if you are not experienced with port forwarding, then you should set the port to 53640. Make sure the protocol you are using is set to UDP.