AWS Exposable Resources
The goal of this repo is to maintain a list of all AWS resources that can be publicly exposed, and eventually, those that can be shared with untrusted accounts (that section is still in development and not included here yet).
The following concepts are applied in this list:
- Resources that could be indirectly exposed through another resource are not included. For example, CloudTrail logs can be sent to an S3 bucket that is public, but it is the S3 bucket that is misconfigured, so CloudTrail is not listed as a resource that can be made public.
- Some resources may require multiple things configured a certain way to be considered public. For example, a Secrets Manager secret that is encrypted with a KMS, would need both the Secret and KMS key to be public for access to the Secret. For the purposes of this list, I consider the Secret resource policy only. Similarly, for Managed ElasticSearch clusters, you need both the resource policy to allow public access, and for it to have a non-VPC IP. I consider only the resource policy. For an EC2, you could create an EC2 with a public IP, but associate a restricted Security Group to it that perhaps later is opened up to allow public access. I view the creation of the EC2 with a public IP, and not the modification of the Securtiy Group to be the action of interest.
Roadmap
I would like this repo to eventually contain the following:
- Sample CLI commands for creating both a private and public resource
- Associated CloudTrail logs for these two events so you can build and test monitoring solutions. For example, you can see sample CloudTrail events for StreamAlert here
- Associated Describe calls on the resources to show what it looks like when these resources are public. For example, you can see sample json responses in CloudMapper's test data here.
Resources that can be made public through resource policies
ECR Repository
Actions:
Lambda
Allows invoking the function
Actions:
- lambda add-permission
Lambda layer
Actions:
- lambda add-layer-version-permission
Serverless Application Repository
Actions:
- serverlessrepo put-application-policy
Backup
Actions:
EFS
TODO: Need to confirm this can actually be shared with other accounts. Some of the doc wording leads me to think this might only be shareable to principals within an account.
Actions:
Glacier
Actions:
- glacier set-vault-access-policy
S3
S3 buckets can be public via policies and ACL. S3 objects can be public via ACL. ACLs can be set at bucket or object creation.
Actions:
- s3api create-bucket
- s3api put-bucket-policy
- s3api put-bucket-acl
- s3api put-object
- s3api put-object-acl
IAM Role
Actions:
- iam create-role
- iam update-assume-role-policy
KMS Keys
Actions:
- kms create-key
- kms create-grant
- kms put-key-policy
Secrets Managers
Actions:
- secretsmanager put-resource-policy
CloudWatch Logs
Actions:
- logs put-resource-policy
- logs put-destination-policy
EventBridge
Only allows sending data into an account
Actions:
- events put-permission
MediaStore
Actions:
- mediastore put-container-policy
ElasticSearch
Actions:
Glue
Actions:
- glue put-resource-policy
SNS
Actions:
- sns create-topic
- sns add-permission
SQS
Actions:
- sqs create-queue
- sqs add-permission
SES
Actions:
Resource that can be made public through sharing APIs
AMI
Actions:
FPGA image
Actions:
EBS snapshot
Actions:
RDS snapshot
Actions:
RDS DB Cluster snapshot
Actions:
Resources that can be made public through network access
API Gateway
There are associated resource policies (see here) that may make this something that should be in multiple categories?
Actions:
- apigateway create-rest-api
- apigateway update-rest-api
- apigateway create-api
CloudFront
Actions:
- cloudfront create-distribution
- cloudfront create-distribution-with-tags
Redshift
Actions:
- redshift create-cluster
- redshift modify-cluster
RDS
Actions:
- rds create-db-instance
- rds modify-db-instance
EC2
Actions:
- ec2 run-instances
- ec2 run-scheduled-instances
Elastic IP
Actions:
- ec2 allocate-address
ECS
Actions:
- ecs create-service
- ecs update-service
- ecs create-task-set
- ecs update-task-set
Global Accelerator
Actions:
- globalaccelerator create-accelerator
ELB
Actions:
- elb create-load-balancer
- elbv2 create-load-balancer
Lightsail
Actions:
- lightsail allocate-static-ip
- lightsail create-distribution
- lightsail create-relational-database
- lightsail update-relational-database
- lightsail create-load-balancer
- lightsail create-instances
Neptune
Actions:
- neptune create-db-instance
ElasticCache
Actions:
- elasticcache create-cache-cluster
EMR
Actions:
- emr create-cluster