Overview

Product video
This is a repackaged open source software product wherein additional charges apply for Citadel security hardening, ongoing image maintenance, release evidence, and US-based support.
Hardened CentOS Stream 10 (ARM) gives teams a production-ready ARM64 operating system baseline for Citadel Hardened Baseline-scoped workloads on AWS.
Move from a general-purpose centos-stream-10 image to a documented, security-focused starting point without spending weeks designing controls, building hardening automation, troubleshooting configuration dependencies, and assembling release evidence. Citadel handles the operating system baseline so your team can focus on your applications and the controls specific to your environment.
What You Get
- Citadel-applied centos-stream-10 stream-10 security hardening designed to support Citadel Hardened Baseline infrastructure requirements
- Security-focused configuration across authentication, account policy, privilege boundaries, audit logging, networking, services, kernel settings, file permissions, and other operating system safeguards
- Current centos-stream-10 package and security updates applied during the controlled image build
- Pre-hardening and post-hardening assessment results, remediation history, and a release-specific evidence report for the exact image release
- A clean, application-neutral AMI with no bundled business applications, security agents, or platform lock-in
- Ongoing Citadel image maintenance and direct access to a US-based support team
Built for Security-Focused and Regulated Workloads
Use this image as a repeatable baseline for:
- Security-focused production workloads
- Regulated development and test environments
- Audit remediation projects
- Golden image programs
- Organizations that need a faster path to a defensible Linux baseline
The AMI helps reduce manual hardening effort and configuration drift across AWS accounts and environments. Infrastructure teams can deploy the same reviewed baseline behind their own network controls, identity model, deployment pipeline, observability stack, backup policy, and workload configuration.
Security and compliance teams also gain release records that are easier to trace directly to the image being deployed.
This image is built for ARM64 EC2 instances and supports AWS Graviton instance families and ARM64-native application stacks.
Deploy and Operate with Confidence
The image is ready for use when launched. Citadel recommends AWS Systems Manager Session Manager (SSM) for administrative access whenever possible so SSH does not need to be exposed to the public Internet.
If SSH is required, use the ec2-user account, your selected EC2 key pair, and tightly scoped network access.
Detailed usage instructions in this listing cover connection methods, accessing hardening evidence, and getting support.
For routine updates, apply centos-stream-10 security patches through your approved change process. When Citadel publishes a new image version, validate it outside production before using a controlled replacement or migration process.
Hardening Evidence
Each Citadel release includes supporting documentation and release-specific hardening evidence. Use the Citadel documentation and Trust Center resources referenced in this listing to review:
- Applied security controls
- Pre-hardening and post-hardening assessment results
- Remediation history
- Release-specific validation evidence
- Documented exceptions, where applicable
US-Based Support Included
Email support@citadelpci.com for help with:
- Choosing the right image
- Understanding hardening behavior
- Patching or upgrade planning
- Locating release evidence
- Troubleshooting image behavior
- Citadel Hardened Baseline review questions related to the operating system baseline
Support requests are handled by Citadel's US-based team.
Scope and Customer Responsibility
This AMI is designed to support Citadel Hardened Baseline infrastructure objectives, but launching a hardened image does not by itself make an application, AWS account, regulated environment, or organization secure or compliant with any external framework.
Customers remain responsible for the security and compliance of their complete environment, including application security, IAM, network segmentation, encryption, key and secret management, logging, monitoring, vulnerability management, backups, incident response, operational procedures, and compliance validation.
Review the provided evidence against your organization's requirements and involve your assessor where appropriate.
Highlights
- Start with centos-stream-10 security settings designed for Citadel Hardened Baseline-scoped AWS workloads.
- Reduce manual baseline work with a maintained, application-neutral AMI that is ready for your approved workloads and tooling.
- Get ongoing image maintenance and seller support for deployment, hardening behavior, patching, and upgrades.
Details
Introducing multi-product solutions
You can now purchase comprehensive solutions tailored to use cases and industries.
Features and programs
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Pricing
- ...
Dimension | Cost/hour |
|---|---|
t4g.small Recommended | $0.14 |
a1.2xlarge | $0.64 |
a1.4xlarge | $0.64 |
a1.large | $0.32 |
a1.medium | $0.32 |
a1.metal | $1.20 |
a1.xlarge | $0.64 |
c6g.12xlarge | $0.64 |
c6g.16xlarge | $1.20 |
c6g.2xlarge | $0.64 |
Vendor refund policy
All fees are non-refundable except where required by law or explicitly stated in a private offer.
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Delivery details
64-bit (Arm) Amazon Machine Image (AMI)
Amazon Machine Image (AMI)
An AMI is a virtual image that provides the information required to launch an instance. Amazon EC2 (Elastic Compute Cloud) instances are virtual servers on which you can run your applications and workloads, offering varying combinations of CPU, memory, storage, and networking resources. You can launch as many instances from as many different AMIs as you need.
Version release notes
Security patches and package updates (August 2026)
Additional details
Usage instructions
Using Hardened CentOS Stream 10 (ARM)
Connect to Your Instance
We recommend using AWS Systems Manager Session Manager (SSM) whenever possible. It provides a secure way to access your instance without exposing SSH to the public Internet.
https://docs.aws.amazon.com/systems-manager/latest/userguide/session-manager.html
If you prefer to use SSH, the default username is ec2-user. Connect using the EC2 key pair you selected when launching the instance:
ssh -i /path/to/your-key.pem ec2-user@<public-ip-address>If SSH is enabled, limit port 22 in your security group to your trusted IP address whenever possible. For production environments, we recommend deploying the instance inside a private VPC and using SSM or another controlled access method.
AWS SSH documentation:
https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/AccessingInstances.html
Hardening Evidence
Documentation, hardening details, and validation evidence for this image are available here:
https://assets.citadelpci.com/evidence/citadel-aws-centos-stream-10-hardened-arm64
Use the documentation to review the image's security baseline, applied controls, validation results, and any documented exceptions.
Support
If you have questions about connecting to the instance, the hardening configuration, or the supporting evidence, contact support@citadelpci.com .
When contacting support, include the product name, AWS Region, AMI ID, instance type, and a short description of the issue. Do not send private keys, passwords, tokens, or other secrets.
Resources
Support
Vendor support
Email support@citadelpci.com for help with deployment, hardening behavior, release evidence, patching and upgrade planning, or PCI DSS questions related to the operating system baseline.
AWS infrastructure support
AWS Support is a one-on-one, fast-response support channel that is staffed 24x7x365 with experienced and technical support engineers. The service helps customers of all sizes and technical abilities to successfully utilize the products and features provided by Amazon Web Services.