Update README.md

Author: Spomky

README.md

@@ -35,7 +35,7 @@ If you feel comfortable writing code, you could try to fix [opened issues where
 
 Do not forget to [follow these best practices](.github/CONTRIBUTING.md).
 
-**If you think you have found a security issue, DO NOT open an issue**. You should submit your issue here. 
+**If you think you have found a security issue, DO NOT open an issue**. [You MUST submit your issue here](https://gitter.im/Spomky/).
 
 # Licence