SUMMARY
How secure are my deployed instances against attacks from public hosts?
ISSUE
By default your instances are not visible to any public hosts. Each instance only becomes visible to the public when you associate an external IP to it. In addition, instances are protected by two layers of security:
- Network ACL blocks all traffic except TCP connections to SSH (22), RDP (3389) and ICMP; and
- Security Group blocks all traffic except those mentioned above and those that originate from instances with the same security group.
RESOLUTION
As a security best practice, you should disassociate your external IP to your instance when you are not connecting to it.