Operational Best Practices for NCSC Cloud Security Principles - AWS Config

Operational Best Practices for NCSC Cloud Security Principles

Conformance packs provide a general-purpose compliance framework designed to enable you to create security, operational or cost-optimization governance checks using managed or custom AWS Config rules and AWS Config remediation actions. Conformance Packs, as sample templates, are not designed to fully ensure compliance with a specific governance or compliance standard. You are responsible for making your own assessment of whether your use of the Services meets applicable legal and regulatory requirements.

The following provides a sample mapping between the UK National Cyber Security Centre (NCSC) Cloud Security Principles and AWS managed Config rules. Each Config rule applies to a specific AWS resource, and relates to one or more UK NCSC Cloud Security Principles controls. A UK NCSC Cloud Security Principles control can be related to multiple Config rules. Refer to the table below for more detail and guidance related to these mappings.

This sample conformance pack template contains mappings to controls within the UK NCSC Cloud Security Principles (National Cyber Security Centre | Cloud security guidance), with such public sector information licensed under the Open Government Licence v3.0. The Open Government Licence should can be accessed here: Open Government Licence for public sector information.

AWS Region: All supported AWS Regions except Middle East (Bahrain)

Control ID AWS Config Rule Guidance
1. Data in transit protection

acm-certificate-expiration-check

Ensure network integrity is protected by ensuring X509 certificates are issued by AWS ACM. These certificates must be valid and unexpired. This rule requires a value for daysToExpiration (AWS Foundational Security Best Practices value: 90). The actual value should reflect your organization's policies.
1. Data in transit protection

alb-http-drop-invalid-header-enabled

Ensure that your Elastic Load Balancers (ELB) are configured to drop http headers. Because sensitive data can exist, enable encryption in transit to help protect that data.
1. Data in transit protection

alb-http-to-https-redirection-check

To help protect data in transit, ensure that your Application Load Balancer automatically redirects unencrypted HTTP requests to HTTPS. Because sensitive data can exist, enable encryption in transit to help protect that data.
1. Data in transit protection

elasticsearch-node-to-node-encryption-check

Ensure node-to-node encryption for Amazon OpenSearch Service is enabled. Node-to-node encryption enables TLS 1.2 encryption for all communications within the Amazon Virtual Private Cloud (Amazon VPC). Because sensitive data can exist, enable encryption in transit to help protect that data.
1. Data in transit protection

elb-acm-certificate-required

Because sensitive data can exist and to help protect data at transit, ensure encryption is enabled for your Elastic Load Balancing. Use AWS Certificate Manager to manage, provision and deploy public and private SSL/TLS certificates with AWS services and internal resources.
1. Data in transit protection

api-gw-ssl-enabled

Ensure Amazon API Gateway REST API stages are configured with SSL certificates to allow backend systems to authenticate that requests originate from API Gateway.
1. Data in transit protection

elbv2-acm-certificate-required

Because sensitive data can exist and to help protect data at transit, ensure encryption is enabled for your Elastic Load Balancing. Use AWS Certificate Manager to manage, provision and deploy public and private SSL/TLS certificates with AWS services and internal resources.
1. Data in transit protection

elb-tls-https-listeners-only

Ensure that your Elastic Load Balancers (ELBs) are configured with SSL or HTTPS listeners. Because sensitive data can exist, enable encryption in transit to help protect that data.
1. Data in transit protection

redshift-require-tls-ssl

Ensure that your Amazon Redshift clusters require TLS/SSL encryption to connect to SQL clients. Because sensitive data can exist, enable encryption in transit to help protect that data.
1. Data in transit protection

s3-bucket-ssl-requests-only

To help protect data in transit, ensure that your Amazon Simple Storage Service (Amazon S3) buckets require requests to use Secure Socket Layer (SSL). Because sensitive data can exist, enable encryption in transit to help protect that data.
2: Asset protection and resilience

ebs-snapshot-public-restorable-check

Manage access to the AWS Cloud by ensuring EBS snapshots are not publicly restorable. EBS volume snapshots can contain sensitive information and access control is required for such accounts.
2: Asset protection and resilience

rds-snapshots-public-prohibited

Manage access to resources in the AWS Cloud by ensuring that Amazon Relational Database Service (Amazon RDS) instances are not public. Amazon RDS database instances can contain sensitive information and principles and access control is required for such accounts.
2: Asset protection and resilience

s3-bucket-public-read-prohibited

Manage access to resources in the AWS Cloud by only allowing authorized users, processes, and devices access to Amazon Simple Storage Service (Amazon S3) buckets. The management of access should be consistent with the classification of the data.
2: Asset protection and resilience

s3-bucket-public-write-prohibited

Manage access to resources in the AWS Cloud by only allowing authorized users, processes, and devices access to Amazon Simple Storage Service (Amazon S3) buckets. The management of access should be consistent with the classification of the data.
2. Asset protection and resilience

api-gw-cache-enabled-and-encrypted

To help protect data at rest, ensure encryption is enabled for your API Gateway stage's cache. Because sensitive data can be captured for the API method, enable encryption at rest to help protect that data.
2. Asset protection and resilience

cloud-trail-encryption-enabled

Because sensitive data may exist and to help protect data at rest, ensure encryption is enabled for your AWS CloudTrail trails.
2. Asset protection and resilience

cloudwatch-log-group-encrypted

To help protect sensitive data at rest, ensure encryption is enabled for your Amazon CloudWatch Log Groups.
2. Asset protection and resilience

dynamodb-table-encrypted-kms

Ensure that encryption is enabled for your Amazon DynamoDB tables. Because sensitive data can exist at rest in these tables, enable encryption at rest to help protect that data. By default, DynamoDB tables are encrypted with an AWS owned customer master key (CMK).
2. Asset protection and resilience

db-instance-backup-enabled

The backup feature of Amazon RDS creates backups of your databases and transaction logs. Amazon RDS automatically creates a storage volume snapshot of your DB instance, backing up the entire DB instance. The system allows you to set specific retention periods to meet your resilience requirements.
2. Asset protection and resilience

dynamodb-autoscaling-enabled

Amazon DynamoDB auto scaling uses the AWS Application Auto Scaling service to adjust provisioned throughput capacity that automatically responds to actual traffic patterns. This enables a table or a global secondary index to increase its provisioned read/write capacity to handle sudden increases in traffic, without throttling.
2. Asset protection and resilience

dynamodb-in-backup-plan

To help with data back-up processes, ensure your Amazon DynamoDB tables are a part of an AWS Backup plan. AWS Backup is a fully managed backup service with a policy-based backup solution. This solution simplifies your backup management and enables you to meet your business and regulatory backup compliance requirements.
2. Asset protection and resilience

ebs-in-backup-plan

To help with data back-up processes, ensure your Amazon Elastic Block Store (Amazon EBS) volumes are a part of an AWS Backup plan. AWS Backup is a fully managed backup service with a policy-based backup solution. This solution simplifies your backup management and enables you to meet your business and regulatory backup compliance requirements.
2. Asset protection and resilience

efs-in-backup-plan

To help with data back-up processes, ensure your Amazon Elastic File System (Amazon EFS) file systems are a part of an AWS Backup plan. AWS Backup is a fully managed backup service with a policy-based backup solution. This solution simplifies your backup management and enables you to meet your business and regulatory backup compliance requirements.
2. Asset protection and resilience

elasticache-redis-cluster-automatic-backup-check

When automatic backups are enabled, Amazon ElastiCache creates a backup of the cluster on a daily basis. The backup can be retained for a number of days as specified by your organization. Automatic backups can help guard against data loss. If a failure occurs, you can create a new cluster, which restores your data from the most recent backup.
2. Asset protection and resilience

elb-cross-zone-load-balancing-enabled

Enable cross-zone load balancing for your Elastic Load Balancers (ELBs) to help maintain adequate capacity and availability. The cross-zone load balancing reduces the need to maintain equivalent numbers of instances in each enabled availability zone. It also improves your application's ability to handle the loss of one or more instances.
2. Asset protection and resilience

elb-deletion-protection-enabled

This rule ensures that Elastic Load Balancing has deletion protection enabled. Use this feature to prevent your load balancer from being accidentally or maliciously deleted, which can lead to loss of availability for your applications.
2. Asset protection and resilience

rds-in-backup-plan

To help with data back-up processes, ensure your Amazon Relational Database Service (Amazon RDS) instances are a part of an AWS Backup plan. AWS Backup is a fully managed backup service with a policy-based backup solution. This solution simplifies your backup management and enables you to meet your business and regulatory backup compliance requirements.
2. Asset protection and resilience

rds-multi-az-support

Multi-AZ support in Amazon Relational Database Service (Amazon RDS) provides enhanced availability and durability for database instances. When you provision a Multi-AZ database instance, Amazon RDS automatically creates a primary database instance, and synchronously replicates the data to a standby instance in a different Availability Zone. Each Availability Zone runs on its own physically distinct, independent infrastructure, and is engineered to be highly reliable. In case of an infrastructure failure, Amazon RDS performs an automatic failover to the standby so that you can resume database operations as soon as the failover is complete.
2. Asset protection and resilience

s3-bucket-replication-enabled

Amazon Simple Storage Service (Amazon S3) Cross-Region Replication (CRR) supports maintaining adequate capacity and availability. CRR enables automatic, asynchronous copying of objects across Amazon S3 buckets to help ensure that data availability is maintained.
2. Asset protection and resilience

s3-bucket-versioning-enabled

Amazon Simple Storage Service (Amazon S3) bucket versioning helps keep multiple variants of an object in the same Amazon S3 bucket. Use versioning to preserve, retrieve, and restore every version of every object stored in your Amazon S3 bucket. Versioning helps you to easily recover from unintended user actions and application failures.
2. Asset protection and resilience

s3-bucket-level-public-access-prohibited

Manage access to resources in the AWS Cloud by ensuring that Amazon Simple Storage Service (Amazon S3) buckets cannot be publicly accessed. This rule helps keeping sensitive data safe from unauthorized remote users by preventing public access at the bucket level.
2. Asset protection and resilience

redshift-cluster-kms-enabled

To help protect data at rest, ensure encryption with AWS Key Management Service (AWS KMS) is enabled for your Amazon Redshift cluster. Because sensitive data can exist at rest in Redshift clusters, enable encryption at rest to help protect that data.
2. Asset protection and resilience

redshift-backup-enabled

To help with data back-up processes, ensure your Amazon Redshift clusters have automated snapshots. When automated snapshots are enabled for a cluster, Redshift periodically takes snapshots of that cluster. By default, Redshift takes a snapshot every eight hours or every 5 GB per node of data changes, or whichever comes first.
2. Asset protection and resilience

s3-account-level-public-access-blocks-periodic

Manage access to resources in the AWS Cloud by ensuring that Amazon Simple Storage Service (Amazon S3) buckets cannot be publicly accessed. This rule helps keeping sensitive data safe from unauthorized remote users by preventing public access. This rule allows you to optionally set the ignorePublicAcls (Config Default: True), blockPublicPolicy (Config Default: True), blockPublicAcls (Config Default: True), and restrictPublicBuckets parameters (Config Default: True). The actual values should reflect your organization's policies.
2. Asset protection and resilience

ssm-document-not-public

Ensure AWS Systems Manager (SSM) documents are not public, as this may allow unintended access to your SSM documents. A public SSM document can expose information about your account, resources and internal processes.
2. Asset protection and resilience

ec2-ebs-encryption-by-default

To help protect data at rest, ensure that encryption is enabled for your Amazon Elastic Block Store (Amazon EBS) volumes. Because sensitive data can exist at rest in these volumes, enable encryption at rest to help protect that data.
2. Asset protection and resilience

efs-encrypted-check

Because sensitive data can exist and to help protect data at rest, ensure encryption is enabled for your Amazon Elastic File System (EFS).
2. Asset protection and resilience

elasticsearch-encrypted-at-rest

Because sensitive data can exist and to help protect data at rest, ensure encryption is enabled for your Amazon OpenSearch Service (OpenSearch Service) domains.
2. Asset protection and resilience

encrypted-volumes

Because sensitive data can exist and to help protect data at rest, ensure encryption is enabled for your Amazon Elastic Block Store (Amazon EBS) volumes.
2. Asset protection and resilience

kms-cmk-not-scheduled-for-deletion

To help protect data at rest, ensure necessary customer master keys (CMKs) are not scheduled for deletion in AWS Key Management Service (AWS KMS). Because key deletion is necessary at times, this rule can assist in checking for all keys scheduled for deletion, in case a key was scheduled unintentionally.
2. Asset protection and resilience

rds-snapshot-encrypted

Ensure that encryption is enabled for your Amazon Relational Database Service (Amazon RDS) snapshots. Because sensitive data can exist at rest, enable encryption at rest to help protect that data.
2. Asset protection and resilience

rds-storage-encrypted

To help protect data at rest, ensure that encryption is enabled for your Amazon Relational Database Service (Amazon RDS) instances. Because sensitive data can exist at rest in Amazon RDS instances, enable encryption at rest to help protect that data.
2. Asset protection and resilience

redshift-cluster-configuration-check

To protect data at rest, ensure that encryption is enabled for your Amazon Redshift clusters. You must also ensure that required configurations are deployed on Amazon Redshift clusters. The audit logging should be enabled to provide information about connections and user activities in the database. This rule requires that a value is set for clusterDbEncrypted (Config Default : TRUE), and loggingEnabled (Config Default: TRUE). The actual values should reflect your organization's policies.
2. Asset protection and resilience

s3-bucket-server-side-encryption-enabled

To help protect data at rest, ensure encryption is enabled for your Amazon Simple Storage Service (Amazon S3) buckets. Because sensitive data can exist at rest in Amazon S3 buckets, enable encryption to help protect that data.
2. Asset protection and resilience

s3-default-encryption-kms

Ensure that encryption is enabled for your Amazon Simple Storage Service (Amazon S3) buckets. Because sensitive data can exist at rest in an Amazon S3 bucket, enable encryption at rest to help protect that data.
2. Asset protection and resilience

sagemaker-endpoint-configuration-kms-key-configured

To help protect data at rest, ensure encryption with AWS Key Management Service (AWS KMS) is enabled for your SageMaker endpoint. Because sensitive data can exist at rest in SageMaker endpoint, enable encryption at rest to help protect that data.
2. Asset protection and resilience

sagemaker-notebook-instance-kms-key-configured

To help protect data at rest, ensure encryption with AWS Key Management Service (AWS KMS) is enabled for your SageMaker notebook. Because sensitive data can exist at rest in SageMaker notebook, enable encryption at rest to help protect that data.
2. Asset protection and resilience

sns-encrypted-kms

To help protect data at rest, ensure that your Amazon Simple Notification Service (Amazon SNS) topics require encryption using AWS Key Management Service (AWS KMS). Because sensitive data can exist at rest in published messages, enable encryption at rest to help protect that data.
2. Asset protection and resilience

lambda-function-public-access-prohibited

Manage access to resources in the AWS Cloud by ensuring AWS Lambda functions cannot be publicly accessed. Public access can potentially lead to degradation of availability of resources.
5. Operational security

api-gw-execution-logging-enabled

API Gateway logging displays detailed views of users who accessed the API and the way they accessed the API. This insight enables visibility of user activities.
5. Operational security

cloud-trail-cloud-watch-logs-enabled

Use Amazon CloudWatch to centrally collect and manage log event activity. Inclusion of AWS CloudTrail data provides details of API call activity within your AWS account.
5. Operational security

cloudtrail-enabled

AWS CloudTrail can help in non-repudiation by recording AWS Management Console actions and API calls. You can identify the users and AWS accounts that called an AWS service, the source IP address where the calls generated, and the timings of the calls. Details of captured data are seen within AWS CloudTrail Record Contents.
5. Operational security

cloudtrail-s3-dataevents-enabled

The collection of Simple Storage Service (Amazon S3) data events helps in detecting any anomalous activity. The details include AWS account information that accessed an Amazon S3 bucket, IP address, and time of event.
5. Operational security

cloudwatch-alarm-action-check

Amazon CloudWatch alarms alert when a metric breaches the threshold for a specified number of evaluation periods. The alarm performs one or more actions based on the value of the metric or expression relative to a threshold over a number of time periods. This rule requires a value for alarmActionRequired (Config Default: True), insufficientDataActionRequired (Config Default: True), okActionRequired (Config Default: False). The actual value should reflect the alarm actions for your environment.
5. Operational security

cw-loggroup-retention-period-check

Ensure a minimum duration of event log data is retained for your log groups to help with troubleshooting and forensics investigations. The lack of available past event log data makes it difficult to reconstruct and identify potentially malicious events.
5. Operational security

account-part-of-organizations

Centralized management of AWS accounts within AWS Organizations helps to ensure that accounts are compliant. The lack of centralized account governance may lead to inconsistent account configurations, which may expose resources and sensitive data.
5. Operational security

restricted-ssh

Amazon Elastic Compute Cloud (Amazon EC2) Security Groups can help manage network access by providing stateful filtering of ingress and egress network traffic to AWS resources. Not allowing ingress (or remote) traffic from 0.0.0.0/0 to port 22 on your resources help you restricting remote access.
5. Operational security

restricted-common-ports

Manage access to resources in the AWS Cloud by ensuring common ports are restricted on Amazon Elastic Compute Cloud (Amazon EC2) security groups. Not restricting access to ports to trusted sources can lead to attacks against the availability, integrity and confidentiality of systems. This rule allows you to optionally set blockedPort1 - blockedPort5 parameters (Config Defaults: 20,21,3389,3306,4333). The actual values should reflect your organization's policies.
5. Operational security

no-unrestricted-route-to-igw

Ensure Amazon EC2 route tables do not have unrestricted routes to an internet gateway. Removing or limiting the access to the internet for workloads within Amazon VPCs can reduce unintended access within your environment.
5. Operational security

elasticsearch-logs-to-cloudwatch

Ensure Amazon OpenSearch Service domains have error logs enabled and streamed to Amazon CloudWatch Logs for retention and response. Domain error logs can assist with security and access audits, and can help to diagnose availability issues.
5. Operational security

ec2-imdsv2-check

Ensure the Instance Metadata Service Version 2 (IMDSv2) method is enabled to help protect access and control of Amazon Elastic Compute Cloud (Amazon EC2) instance metadata. The IMDSv2 method uses session-based controls. With IMDSv2, controls can be implemented to restrict changes to instance metadata.
5. Operational security

ec2-instance-managed-by-systems-manager

An inventory of the software platforms and applications within the organization is possible by managing Amazon Elastic Compute Cloud (Amazon EC2) instances with AWS Systems Manager. Use AWS Systems Manager to provide detailed system configurations, operating system patch levels, services name and type, software installations, application name, publisher and version, and other details about your environment.
5. Operational security

ec2-managedinstance-association-compliance-status-check

Use AWS Systems Manager Associations to help with inventory of software platforms and applications within an organization. AWS Systems Manager assigns a configuration state to your managed instances and allows you to set baselines of operating system patch levels, software installations, application configurations, and other details about your environment.
5. Operational security

ec2-managedinstance-patch-compliance-status-check

Enable this rule to help with identification and documentation of Amazon Elastic Compute Cloud (Amazon EC2) vulnerabilities. The rule checks if Amazon EC2 instance patch compliance in AWS Systems Manager as required by your organization's policies and procedures.
5. Operational security

elb-logging-enabled

Elastic Load Balancing activity is a central point of communication within an environment. Ensure ELB logging is enabled. The collected data provides detailed information about requests sent to the ELB. Each log contains information such as the time the request was received, the client's IP address, latencies, request paths, and server responses.
5. Operational security

guardduty-enabled-centralized

Amazon GuardDuty can help to monitor and detect potential cybersecurity events by using threat intelligence feeds. These include lists of malicious IPs and machine learning to identify unexpected, unauthorized, and malicious activity within your AWS Cloud environment.
5. Operational security

guardduty-non-archived-findings

Amazon GuardDuty helps you understand the impact of an incident by classifying findings by severity: low, medium, and high. You can use these classifications for determining remediation strategies and priorities. This rule allows you to optionally set the daysLowSev (Config Default: 30), daysMediumSev (Config Default: 7), and daysHighSev (Config Default: 1) for non-archived findings, as required by your organization's policies.
5. Operational security

multi-region-cloudtrail-enabled

AWS CloudTrail records AWS Management Console actions and API calls. You can identify which users and accounts called AWS, the source IP address from where the calls were made, and when the calls occurred. CloudTrail will deliver log files from all AWS Regions to your S3 bucket if MULTI_REGION_CLOUD_TRAIL_ENABLED is enabled. Additionally, when AWS launches a new Region, CloudTrail will create the same trail in the new Region. As a result, you will receive log files containing API activity for the new Region without taking any action.
5. Operational security

rds-logging-enabled

To help with logging and monitoring within your environment, ensure Amazon Relational Database Service (Amazon RDS) logging is enabled. With Amazon RDS logging, you can capture events such as connections, disconnections, queries, or tables queried.
5. Operational security

redshift-cluster-maintenancesettings-check

This rule ensures that Amazon Redshift clusters have the preferred settings for your organization. Specifically, that they have preferred maintenance windows and automated snapshot retention periods for the database. This rule requires you to set the allowVersionUpgrade. The default is true. It also lets you optionally set the preferredMaintenanceWindow (the default is sat:16:00-sat:16:30), and the automatedSnapshotRetentionPeriod (the default is 1). The actual values should reflect your organization's policies.
5. Operational security

s3-bucket-logging-enabled

Amazon Simple Storage Service (Amazon S3) server access logging provides a method to monitor the network for potential cybersecurity events. The events are monitored by capturing detailed records for the requests that are made to an Amazon S3 bucket. Each access log record provides details about a single access request. The details include the requester, bucket name, request time, request action, response status, and an error code, if relevant.
5. Operational security

securityhub-enabled

AWS Security Hub helps to monitor unauthorized personnel, connections, devices, and software. AWS Security Hub aggregates, organizes, and prioritizes the security alerts, or findings, from multiple AWS services. Some such services are Amazon Security Hub, Amazon Inspector, Amazon Macie, AWS Identity and Access Management (IAM) Access Analyzer, and AWS Firewall Manager, and AWS Partner solutions.
5. Operational security

vpc-flow-logs-enabled

The VPC flow logs provide detailed records for information about the IP traffic going to and from network interfaces in your Amazon Virtual Private Cloud (Amazon VPC). By default, the flow log record includes values for the different components of the IP flow, including the source, destination, and protocol.
5. Operational security

wafv2-logging-enabled

To help with logging and monitoring within your environment, enable AWS WAF (V2) logging on regional and global web ACLs. AWS WAF logging provides detailed information about the traffic that is analyzed by your web ACL. The logs record the time that AWS WAF received the request from your AWS resource, information about the request, and an action for the rule that each request matched.
5. Operational security

lambda-dlq-check

Enable this rule to help notify the appropriate personnel through Amazon Simple Queue Service (Amazon SQS) or Amazon Simple Notification Service (Amazon SNS) when a function has failed.
5. Operational security

rds-enhanced-monitoring-enabled

Enable Amazon Relational Database Service (Amazon RDS) to help monitor Amazon RDS availability. This provides detailed visibility into the health of your Amazon RDS database instances. When the Amazon RDS storage is using more than one underlying physical device, Enhanced Monitoring collects the data for each device. Also, when the Amazon RDS database instance is running in a Multi-AZ deployment, the data for each device on the secondary host is collected, and the secondary host metrics.
6. Personnel security security-awareness-program-exists (process check) Establish and maintain a security awareness program for your organization. Security awareness programs educate employees on how to protect their organization from various security breaches or incidents.
7. Secure development

codebuild-project-envvar-awscred-check

Ensure authentication credentials AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY do not exist within AWS Codebuild project environments. Do not store these variables in clear text. Storing these variables in clear text leads to unintended data exposure and unauthorized access.
7. Secure development

codebuild-project-source-repo-url-check

Ensure the GitHub or Bitbucket source repository URL does not contain personal access tokens, user name and password within AWS Codebuild project environments. Use OAuth instead of personal access tokens or a user name and password to grant authorization for accessing GitHub or Bitbucket repositories.
9. Secure user management

access-keys-rotated

The credentials are audited for authorized devices, users, and processes by ensuring IAM access keys are rotated as per organizational policy. Changing the access keys on a regular schedule is a security best practice. It shortens the period an access key is active and reduces the business impact if the keys are compromised. This rule requires an access key rotation value (Config Default: 90). The actual value should reflect your organization's policies.
9. Secure user management

iam-group-has-users-check

AWS Identity and Access Management (IAM) can help you incorporate the principles of least privilege and separation of duties with access permissions and authorizations, by ensuring that IAM groups have at least one IAM user. Placing IAM users in groups based on their associated permissions or job function is one way to incorporate least privilege.
9. Secure user management

iam-policy-no-statements-with-admin-access

AWS Identity and Access Management (IAM) can help you incorporate the principles of least privilege and separation of duties with access permissions and authorizations, restricting policies from containing "Effect": "Allow" with "Action": "*" over "Resource": "*". Allowing users to have more privileges than needed to complete a task may violate the principle of least privilege and separation of duties.
9. Secure user management

iam-root-access-key-check

Access to systems and assets can be controlled by checking that the root user does not have access keys attached to their AWS Identity and Access Management (IAM) role. Ensure that the root access keys are deleted. Instead, create and use role-based AWS accounts to help to incorporate the principle of least functionality.
9. Secure user management

iam-user-group-membership-check

AWS Identity and Access Management (IAM) can help you restrict access permissions and authorizations, by ensuring IAM users are members of at least one group. Allowing users more privileges than needed to complete a task may violate the principle of least privilege and separation of duties.
9. Secure user management

iam-user-no-policies-check

This rule ensures AWS Identity and Access Management (IAM) policies are attached only to groups or roles to control access to systems and assets. Assigning privileges at the group or the role level helps to reduce opportunity for an identity to receive or retain excessive privileges.
9. Secure user management

iam-user-unused-credentials-check

AWS Identity and Access Management (IAM) can help you with access permissions and authorizations by checking for IAM passwords and access keys that are not used for a specified time period. If these unused credentials are identified, you should disable and/or remove the credentials, as this may violate the principle of least privilege. This rule requires you to set a value to the maxCredentialUsageAge (Config Default: 90). The actual value should reflect your organization's policies.
9. Secure user management

iam-customer-policy-blocked-kms-actions

AWS Identity and Access Management (IAM) can help you incorporate the principles of least privilege and separation of duties with access permissions and authorizations, restricting policies from containing blocked actions on all AWS Key Management Service keys. Having more privileges than needed to complete a task may violate the principle of least privilege and separation of duties. This rule allows you to set the blockedActionsPatterns parameter. (AWS Foundational Security Best Practices value: kms:Decrypt, kms:ReEncryptFrom). The actual values should reflect your organization's policies
9. Secure user management

iam-inline-policy-blocked-kms-actions

Ensure an AWS Identity and Access Management (IAM) user, IAM role or IAM group does not have an inline policy to allow blocked actions on all AWS Key Management Service keys. AWS recommends to use managed policies instead of inline policies. The managed policies allow reusability, versioning, rolling back, and delegating permissions management. This rule allows you to set the blockedActionsPatterns parameter. (AWS Foundational Security Best Practices value: kms:Decrypt, kms:ReEncryptFrom). The actual values should reflect your organization's policies.
9. Secure user management

iam-policy-no-statements-with-full-access

Ensure IAM Actions are restricted to only those actions that are needed. Allowing users to have more privileges than needed to complete a task may violate the principle of least privilege and separation of duties.
10. Identity and authentication

emr-kerberos-enabled

The access permissions and authorizations can be managed and incorporated with the principles of least privilege and separation of duties, by enabling Kerberos for Amazon EMR clusters. In Kerberos, the services and the users that need to authenticate are known as principals. The principals exist within a Kerberos realm. Within the realm, a Kerberos server is known as the key distribution center (KDC). It provides a means for the principals to authenticate. The KDC authenticates by issuing tickets for authentication. The KDC maintains a database of the principals within its realm, their passwords, and other administrative information about each principal.
10. Identity and authentication

iam-no-inline-policy-check

Ensure an AWS Identity and Access Management (IAM) user, IAM role or IAM group does not have an inline policy to control access to systems and assets. AWS recommends to use managed policies instead of inline policies. The managed policies allow reusability, versioning and rolling back, and delegating permissions management.
10. Identity and authentication

iam-password-policy

The identities and the credentials are issued, managed, and verified based on an organizational IAM password policy. They meet or exceed requirements as stated by NIST SP 800-63 and the AWS Foundational Security Best Practices standard for password strength. This rule allows you to optionally set RequireUppercaseCharacters (AWS Foundational Security Best Practices value: true), RequireLowercaseCharacters (AWS Foundational Security Best Practices value: true), RequireSymbols (AWS Foundational Security Best Practices value: true), RequireNumbers (AWS Foundational Security Best Practices value: true), MinimumPasswordLength (AWS Foundational Security Best Practices value: 14), PasswordReusePrevention (AWS Foundational Security Best Practices value: 24), and MaxPasswordAge (AWS Foundational Security Best Practices value: 90) for your IAM Password Policy. The actual values should reflect your organization's policies.
10. Identity and authentication

iam-user-mfa-enabled

Enable this rule to restrict access to resources in the AWS Cloud. This rule ensures multi-factor authentication (MFA) is enabled for all IAM users. MFA adds an extra layer of protection on top of a user name and password. Reduce the incidents of compromised accounts by requiring MFA for IAM users.
10. Identity and authentication

mfa-enabled-for-iam-console-access

Manage access to resources in the AWS Cloud by ensuring that MFA is enabled for all AWS Identity and Access Management (IAM) users that have a console password. MFA adds an extra layer of protection on top of a user name and password. By requiring MFA for IAM users, you can reduce incidents of compromised accounts and keep sensitive data from being accessed by unauthorized users.
10. Identity and authentication

root-account-hardware-mfa-enabled

Manage access to resources in the AWS Cloud by ensuring hardware MFA is enabled for the root user. The root user is the most privileged user in an AWS account. The MFA adds an extra layer of protection for a user name and password. By requiring MFA for the root user, you can reduce the incidents of compromised AWS accounts.
10. Identity and authentication

root-account-mfa-enabled

Manage access to resources in the AWS Cloud by ensuring MFA is enabled for the root user. The root user is the most privileged user in an AWS account. The MFA adds an extra layer of protection for a user name and password. By requiring MFA for the root user, you can reduce the incidents of compromised AWS accounts.
10. Identity and authentication

secretsmanager-rotation-enabled-check

This rule ensures AWS Secrets Manager secrets have rotation enabled. Rotating secrets on a regular schedule can shorten the period a secret is active, and potentially reduce the business impact if the secret is compromised.
10. Identity and authentication

secretsmanager-scheduled-rotation-success-check

This rule ensures that AWS Secrets Manager secrets have rotated successfully according to the rotation schedule. Rotating secrets on a regular schedule can shorten the period that a secret is active, and potentially reduce the business impact if it is compromised.
10. Identity and authentication

ecs-task-definition-user-for-host-mode-check

If a task definition has elevated privileges it is because the customer has specifically opted-in to those configurations. This control checks for unexpected privilege escalation when a task definition has host networking enabled but the customer has not opted-in to elevated privileges.
11. External interface protection

alb-waf-enabled

Ensure AWS WAF is enabled on Elastic Load Balancers (ELB) to help protect web applications. A WAF helps to protect your web applications or APIs against common web exploits. These web exploits may affect availability, compromise security, or consume excessive resources within your environment.
11. External interface protection

dms-replication-not-public

Manage access to the AWS Cloud by ensuring DMS replication instances cannot be publicly accessed. DMS replication instances can contain sensitive information and access control is required for such accounts.
11. External interface protection

ec2-instances-in-vpc

Deploy Amazon Elastic Compute Cloud (Amazon EC2) instances within an Amazon Virtual Private Cloud (Amazon VPC) to enable secure communication between an instance and other services within the amazon VPC, without requiring an internet gateway, NAT device, or VPN connection. All traffic remains securely within the AWS Cloud. Because of their logical isolation, domains that reside within an Amazon VPC have an extra layer of security when compared to domains that use public endpoints. Assign Amazon EC2 instances to an Amazon VPC to properly manage access.
11. External interface protection

no-unrestricted-route-to-igw

Ensure Amazon EC2 route tables do not have unrestricted routes to an internet gateway. Removing or limiting the access to the internet for workloads within Amazon VPCs can reduce unintended access within your environment.
11. External interface protection

s3-bucket-level-public-access-prohibited

Manage access to resources in the AWS Cloud by ensuring that Amazon Simple Storage Service (Amazon S3) buckets cannot be publicly accessed. This rule helps keeping sensitive data safe from unauthorized remote users by preventing public access at the bucket level.
11. External interface protection

subnet-auto-assign-public-ip-disabled

Manage access to the AWS Cloud by ensuring Amazon Virtual Private Cloud (VPC) subnets are not automatically assigned a public IP address. Amazon Elastic Compute Cloud (EC2) instances that are launched into subnets that have this attribute enabled have a public IP address assigned to their primary network interface.
11. External interface protection

autoscaling-launch-config-public-ip-disabled

If you configure your Network Interfaces with a public IP address, then the associated resources to those Network Interfaces are reachable from the internet. EC2 resources should not be publicly accessible, as this may allow unintended access to your applications or servers.
11. External interface protection

redshift-enhanced-vpc-routing-enabled

Enhanced VPC routing forces all COPY and UNLOAD traffic between the cluster and data repositories to go through your Amazon VPC. You can then use VPC features such as security groups and network access control lists to secure network traffic. You can also use VPC flow logs to monitor network traffic.
11. External interface protection

api-gw-associated-with-waf

AWS WAF enables you to configure a set of rules (called a web access control list (web ACL)) that allow, block, or count web requests based on customizable web security rules and conditions that you define. Ensure your Amazon API Gateway stage is associated with a WAF Web ACL to protect it from malicious attacks
11. External interface protection

s3-account-level-public-access-blocks-periodic

Manage access to resources in the AWS Cloud by ensuring that Amazon Simple Storage Service (Amazon S3) buckets cannot be publicly accessed. This rule helps keeping sensitive data safe from unauthorized remote users by preventing public access. This rule allows you to optionally set the ignorePublicAcls (Config Default: True), blockPublicPolicy (Config Default: True), blockPublicAcls (Config Default: True), and restrictPublicBuckets parameters (Config Default: True). The actual values should reflect your organization's policies.
11. External interface protection

ssm-document-not-public

Ensure AWS Systems Manager (SSM) documents are not public, as this may allow unintended access to your SSM documents. A public SSM document can expose information about your account, resources and internal processes.
11. External interface protection

ec2-instance-no-public-ip

Manage access to the AWS Cloud by ensuring Amazon Elastic Compute Cloud (Amazon EC2) instances cannot be publicly accessed. Amazon EC2 instances can contain sensitive information and access control is required for such accounts.
11. External interface protection

elasticsearch-in-vpc-only

Manage access to the AWS Cloud by ensuring Amazon OpenSearch Service (OpenSearch Service) Domains are within an Amazon Virtual Private Cloud (Amazon VPC). An OpenSearch Service domain within an Amazon VPC enables secure communication between OpenSearch Service and other services within the Amazon VPC without the need for an internet gateway, NAT device, or VPN connection.
11. External interface protection

emr-master-no-public-ip

Manage access to the AWS Cloud by ensuring Amazon EMR cluster master nodes cannot be publicly accessed. Amazon EMR cluster master nodes can contain sensitive information and access control is required for such accounts.
11. External interface protection

restricted-ssh

Amazon Elastic Compute Cloud (Amazon EC2) Security Groups can help manage network access by providing stateful filtering of ingress and egress network traffic to AWS resources. Not allowing ingress (or remote) traffic from 0.0.0.0/0 to port 22 on your resources help you restricting remote access.
11. External interface protection

ec2-instances-in-vpc

Deploy Amazon Elastic Compute Cloud (Amazon EC2) instances within an Amazon Virtual Private Cloud (Amazon VPC) to enable secure communication between an instance and other services within the amazon VPC, without requiring an internet gateway, NAT device, or VPN connection. All traffic remains securely within the AWS Cloud. Because of their logical isolation, domains that reside within an Amazon VPC have an extra layer of security when compared to domains that use public endpoints. Assign Amazon EC2 instances to an Amazon VPC to properly manage access.
11. External interface protection

internet-gateway-authorized-vpc-only

Manage access to resources in the AWS Cloud by ensuring that internet gateways are only attached to authorized Amazon Virtual Private Cloud (Amazon VPC). Internet gateways allow bi-directional internet access to and from the Amazon VPC that can potentially lead to unauthorized access to Amazon VPC resources.
11. External interface protection

lambda-inside-vpc

Deploy AWS Lambda functions within an Amazon Virtual Private Cloud (Amazon VPC) for a secure communication between a function and other services within the Amazon VPC. With this configuration, there is no requirement for an internet gateway, NAT device, or VPN connection. All the traffic remains securely within the AWS Cloud. Because of their logical isolation, domains that reside within an Amazon VPC have an extra layer of security when compared to domains that use public endpoints. To properly manage access, AWS Lambda functions should be assigned to a VPC.
11. External interface protection

rds-instance-public-access-check

Manage access to resources in the AWS Cloud by ensuring that Amazon Relational Database Service (Amazon RDS) instances are not public. Amazon RDS database instances can contain sensitive information, and principles and access control is required for such accounts.
11. External interface protection

redshift-cluster-public-access-check

Manage access to resources in the AWS Cloud by ensuring that Amazon Redshift clusters are not public. Amazon Redshift clusters can contain sensitive information and principles and access control is required for such accounts.
11. External interface protection

restricted-common-ports

Manage access to resources in the AWS Cloud by ensuring common ports are restricted on Amazon Elastic Compute Cloud (Amazon EC2) security groups. Not restricting access to ports to trusted sources can lead to attacks against the availability, integrity and confidentiality of systems. This rule allows you to optionally set blockedPort1 - blockedPort5 parameters (Config Defaults: 20,21,3389,3306,4333). The actual values should reflect your organization's policies.
11. External interface protection

sagemaker-notebook-no-direct-internet-access

Manage access to resources in the AWS Cloud by ensuring that Amazon SageMaker notebooks do not allow direct internet access. By preventing direct internet access, you can keep sensitive data from being accessed by unauthorized users.
11. External interface protection

vpc-default-security-group-closed

Amazon Elastic Compute Cloud (Amazon EC2) security groups can help in the management of network access by providing stateful filtering of ingress and egress network traffic to AWS resources. Restricting all the traffic on the default security group helps in restricting remote access to your AWS resources.
11. External interface protection

vpc-sg-open-only-to-authorized-ports

Manage access to resources in the AWS Cloud by ensuring common ports are restricted on Amazon Elastic Compute Cloud (Amazon EC2) Security Groups. Not restricting access on ports to trusted sources can lead to attacks against the availability, integrity and confidentiality of systems. By restricting access to resources within a security group from the internet (0.0.0.0/0) remote access can be controlled to internal systems.
11. External interface protection

lambda-function-public-access-prohibited

Manage access to resources in the AWS Cloud by ensuring AWS Lambda functions cannot be publicly accessed. Public access can potentially lead to degradation of availability of resources.
11. External interface protection

s3-bucket-public-read-prohibited

Manage access to resources in the AWS Cloud by only allowing authorized users, processes, and devices access to Amazon Simple Storage Service (Amazon S3) buckets. The management of access should be consistent with the classification of the data.
11. External interface protection

s3-bucket-public-write-prohibited

Manage access to resources in the AWS Cloud by only allowing authorized users, processes, and devices access to Amazon Simple Storage Service (Amazon S3) buckets. The management of access should be consistent with the classification of the data.
11. External interface protection

rds-snapshots-public-prohibited

Manage access to resources in the AWS Cloud by ensuring that Amazon Relational Database Service (Amazon RDS) instances are not public. Amazon RDS database instances can contain sensitive information and principles and access control is required for such accounts.
12. Secure service administration

iam-root-access-key-check

Access to systems and assets can be controlled by checking that the root user does not have access keys attached to their AWS Identity and Access Management (IAM) role. Ensure that the root access keys are deleted. Instead, create and use role-based AWS accounts to help to incorporate the principle of least functionality.
13. Audit information for users

cloud-trail-log-file-validation-enabled

Utilize AWS CloudTrail log file validation to check the integrity of CloudTrail logs. Log file validation helps determine if a log file was modified or deleted or unchanged after CloudTrail delivered it. This feature is built using industry standard algorithms: SHA-256 for hashing and SHA-256 with RSA for digital signing. This makes it computationally infeasible to modify, delete or forge CloudTrail log files without detection.
13. Audit information for users

cloudtrail-security-trail-enabled

This rule helps ensure the use of AWS recommended security best practices for AWS CloudTrail, by checking for the enablement of multiple settings. These include the use of log encryption, log validation, and enabling AWS CloudTrail in multiple regions.
13. Audit information for users

cloud-trail-cloud-watch-logs-enabled

Use Amazon CloudWatch to centrally collect and manage log event activity. Inclusion of AWS CloudTrail data provides details of API call activity within your AWS account.
13. Audit information for users

cloudtrail-enabled

AWS CloudTrail can help in non-repudiation by recording AWS Management Console actions and API calls. You can identify the users and AWS accounts that called an AWS service, the source IP address where the calls generated, and the timings of the calls. Details of captured data are seen within AWS CloudTrail Record Contents.

Template

The template is available on GitHub: Operational Best Practices for NCSC Cloud Security Principles.