CloudTrail is an amazing source of data, rich with API call history, allowing us to monitor who is attempting to do what within our AWS accounts.
However, it isn’t all sunshine and rainbows. As every call is logged (including assumption of role, switching of roles and even creation of a log stream), we end up with a lot of logging to digest.
Since we released our Slack bot for CloudTrail events, in the over 400 Million CloudTrail events we have monitored, we have determined that users only want to be notified of 1 in 25,000 CloudTrail events. That is a really high signal to noise ratio!
We have cherry picked some interesting CloudTrail events that our Slack bot users are monitoring for better security. The best news is that we can help you stay on top of these with a slack notification on each occurrence. Try it out!
Security CloudTrail Events
We’re starting with something basic here, but there is a reason for it. Almost every AWS user has an account where they don’t anticipate frequent login activity (production for example). Getting notified of access attempts to such black boxes can be advantageous.
StopLogging is an event type that comes from CloudTrail itself. Monitoring this event type can help you catch anyone deactivating CloudTrail logging, be that maliciously or otherwise.
These two VPC changes are worth monitoring. New ACL entries and routes in your route tables can expose new attack vectors to your infrastructure and are handy for your SecOps team to monitor.
Monitoring changes to Security Group ingress and egress settings is a powerful capability, and is worth listening out for.
These are Elastic Load Balancer specific security group events and worth listening out for too. Here we monitor changes in which security groups are selected.
These are the same as above, but of the RDS flavour and still worth monitoring, especially for internet facing RDS instances.
Don’t forget you can track all these events in Slack using our free CloudTrail for Slack bot.
Next time we’ll dive deep into which IAM CloudTrail events SecOps teams should consider listening out for. If you can’t wait until then, you can check out a more comprehensive list of CloudTrail events here.