HDF System

Describes a system's authorization boundary, components, and interconnections. Maps to OSCAL SSP system-characteristics and FedRAMP system inventory.


Version	`v3.1.0`
`$id`	`https://mitre.github.io/hdf-libs/schemas/hdf-system/v3.1.0`
Download	hdf-system.schema.json

Properties

Field	Type	Required	Description
`systemId`	`string` (uuid)	no	Stable UUID (RFC 4122) for this system. Enables cross-document correlation independent of file location. Optional in casual use, expected in production documents.
`owner`	`Identity`	no	Team or individual responsible for this system's authorization and compliance. Maps to OSCAL responsible-party with role 'system-owner'.
`name`	`string`	yes	Human-readable system name. Example: 'Enterprise Portal Production'.
`identifier`	`string`	no	System identifier from an authoritative source. Example: eMASS system ID, FedRAMP package ID.
`identifierScheme`	`string` (uri-reference)	no	URI identifying the scheme of the system identifier. Example: 'https://emass.mil', 'https://fedramp.gov'.
`description`	`string`	no	Description of the system's purpose and mission.
`authorizationStatus`	`Authorization_Status`	no	Current Authorization to Operate (ATO) status.
`authorizationDate`	`string` (date-time)	no	Date the current authorization status was granted. ISO 8601 format.
`categorizationLevel`	`Categorization_Level`	no	FIPS 199 security categorization (impact level).
`boundaryDescription`	`string`	no	Description of the system's authorization boundary. Example: network CIDR blocks, cloud VPC IDs, physical locations.
`components`	`Component`[]	yes	System components within the authorization boundary. Uses the full polymorphic Component type with stable identity (componentId), external references, and SBOM support.
`controlDesignations`	`Control_Designation`[]	no	Declares which controls are common, hybrid, or system-specific, and which component provides them. Maps to NIST SP 800-53 control designations and OSCAL leveraged-authorizations.
`dataFlows`	`Data_Flow`[]	no	Inter-component data flows describing how components communicate. Supports local, cross-system, and external flows. Replaces the interconnections[] field.
`labels`	Map<string, `string`>	no	Optional key-value labels for grouping and querying systems.
`integrity`	`Integrity`	no	Cryptographic integrity information for verifying this system document has not been tampered with.
`version`	`string`	no	Version of this system document.
`generator`	`Generator`	no	Information about the tool that generated this system document.

Example

json

{
  "name": "Enterprise Portal Production",
  "identifier": "SYS-2024-00142",
  "identifierScheme": "https://emass.mil",
  "authorizationStatus": "authorized",
  "authorizationDate": "2025-06-15T00:00:00Z",
  "categorizationLevel": "moderate",
  "boundaryDescription": "All resources in prod VPC (10.0.0.0/16)",
  "components": [
    {
      "name": "WebTier",
      "type": "application",
      "componentId": "aaaaaaaa-bbbb-cccc-dddd-eeeeeeeeeeee",
      "description": "RHEL 9 web servers running the portal",
      "baselineRefs": [
        "RHEL9-STIG",
        "DISA-Container-STIG"
      ],
      "sbomRef": "https://artifacts.agency.gov/sbom/webtier-2026-03.cdx.json",
      "sbomFormat": "cyclonedx"
    },
    {
      "name": "DatabaseTier",
      "type": "database",
      "componentId": "11111111-2222-3333-4444-555555555555",
      "baselineRefs": [
        "PostgreSQL-15-STIG"
      ]
    }
  ],
  "dataFlows": [
    {
      "from": "aaaaaaaa-bbbb-cccc-dddd-eeeeeeeeeeee",
      "to": "11111111-2222-3333-4444-555555555555",
      "protocol": "jdbc",
      "port": 5432,
      "direction": "unidirectional",
      "description": "Web tier connects to database"
    }
  ]
}

Embedded Primitives

These types are embedded from shared primitive schemas.

amendments/v3.1.0

Override_Type

The type of amendment, aligned with FedRAMP deviation request categories. 'waiver': risk accepted by Authorizing Official. 'attestation': manually verified by assessor. 'poam': remediation tracked (no status change). 'inherited': control provided by another component or system. 'falsePositive': scanner incorrectly identified a finding — for compliance scans (STIG, CIS), the check actually passes, so status is typically set to 'passed'; for vulnerability scans (CVE, SCA), the flagged vulnerability does not apply to this system, so status is typically set to 'notApplicable'. The disposition field on the requirement distinguishes false positives from genuinely not-applicable findings. 'riskAdjustment': impact score adjusted based on environmental context (FedRAMP Risk Adjustment); does not change pass/fail status, only impact via the impact field. 'operationalRequirement': deviation required by operational constraints (FedRAMP Operational Requirement); the finding cannot be remediated because the system requires the affected functionality. Remains an open risk.

Impact_Override

An override to the requirement's impact score. The prior impact is the original result value or the preceding override in the chain.

Field	Type	Required	Description
`value`	`number`	yes	The overridden impact score (0.0–1.0).

Standalone_Override

A standalone amendment that modifies a requirement's compliance status and/or impact score. At least one of status or impact must be set. Extends the inline Override concept with requirementId and baselineRef for use outside of results documents.

Field	Type	Required	Description
`type`	`Override_Type`	yes	The type of amendment.
`requirementId`	`string`	yes	The ID of the requirement being amended. Must match a requirement ID in the referenced baseline.
`baselineRef`	`string`	no	Name of the baseline containing the requirement. Required when the system has multiple baselines with potentially overlapping requirement IDs.
`status`	`Result_Status`	no	The new status this amendment sets. Optional when only impact is being overridden.
`impact`	`Impact_Override`	no	Override to the requirement's impact score. At least one of status or impact must be set.
`reason`	`string`	yes	Justification for this amendment.
`appliedBy`	`Identity`	yes	Identity of who applied this amendment.
`appliedAt`	`string` (date-time)	yes	When this amendment was applied. ISO 8601 format.
`expiresAt`	`string` (date-time)	yes	When this amendment expires and must be reviewed. No permanent amendments. ISO 8601 format.
`evidence`	`Evidence`[]	no	Supporting evidence (screenshots, logs, URLs, documents).
`signature`	`Signature`	no	Digital signature for non-repudiation.
`previousChecksum`	`Checksum`	no	Checksum of the prior amendment in the chain. Creates a tamper-evident linked list. Null for the first amendment.
`milestones`	`Milestone`[]	no	Remediation milestones (primarily for POA&M type amendments).
`inheritedFrom`	`string` (uuid)	no	componentId of the local component that provides this control. Set when the provider is in the same system. Omit for external or cross-system providers; the reason field explains the source. Primarily used with type 'inherited'.
`componentRef`	`string` (uuid)	no	componentId of the component this amendment is scoped to. When set, the amendment only applies to the specified component. When omitted, the amendment applies system-wide.

Example

json

{
  "type": "waiver",
  "requirementId": "SV-257777",
  "baselineRef": "RHEL9-STIG",
  "status": "passed",
  "reason": "Compensating control: session timeout set to 15 min",
  "appliedBy": {
    "type": "email",
    "identifier": "ao@agency.gov"
  },
  "appliedAt": "2026-01-15T10:00:00Z",
  "expiresAt": "2026-06-30T00:00:00Z",
  "evidence": [
    {
      "type": "url",
      "data": "https://jira.agency.gov/CYBER-4521",
      "description": "ISSM approval with compensating control documentation"
    }
  ]
}

common/v3.1.0

Hash_Algorithm

Supported cryptographic hash algorithms for checksums and integrity verification.

Requirement_Group

Describes a group of requirements, such as those defined in a single file.

Field	Type	Required	Description
`id`	`string`	yes	The unique identifier for the group. Example: the relative path to the file specifying the requirements.
`title`	`string`	no	The title of the group - should be human readable.
`requirements`	`string`[]	yes	The set of requirements as specified by their ids in this group. Example: 'SV-238196'.

Dependency

A dependency for a baseline. Can include relative paths or URLs for where to find the dependency.

Field	Type	Required	Description
`name`	`string`	no	The name or assigned alias.
`url`	`string` (uri-reference)	no	The address of the dependency.
`branch`	`string`	no	The branch name for a git repo.
`path`	`string`	no	The relative path if the dependency is locally available.
`statusMessage`	`string`	no	The reason for the status if it is 'failed' or 'skipped'.
`status`	`string`	no	The status. Should be: 'loaded', 'failed', or 'skipped'.
`git`	`string` (uri)	no	The location of the git repo. Example: 'https://github.com/my-org/ubuntu-22.04-stig-baseline.git'.
`supermarket`	`string`	no	The 'user/profilename' attribute for a Supermarket server.
`compliance`	`string`	no	The 'user/profilename' attribute for an Automate server.

Example

json

{
  "name": "ubuntu-22.04-baseline",
  "url": "https://github.com/my-org/ubuntu-22.04-stig-baseline",
  "git": "https://github.com/my-org/ubuntu-22.04-stig-baseline.git",
  "branch": "main",
  "status": "loaded"
}

Reference

A reference to an external document.

Source_Location

The explicit location of a requirement within source code.

Field	Type	Required	Description
`ref`	`string`	no	Path to the file that this requirement originates from.
`line`	`number`	no	The line on which this requirement is located.

Example

json

{
  "ref": "controls/SV-260476.rb",
  "line": 1
}

Supported_Platform

A supported platform target. Example: the platform name being 'ubuntu'.

Field	Type	Required	Description
`platformFamily`	`string`	no	The platform family. Example: 'redhat'.
`platformName`	`string`	no	The platform name - can include wildcards. Example: 'debian'.
`platform`	`string`	no	The location of the platform. Can be: 'os', 'aws', 'azure', or 'gcp'.
`release`	`string`	no	The release of the platform. Example: '20.04' for 'ubuntu'.

Checksum

Cryptographic checksum for baseline integrity verification.

Field	Type	Required	Description
`algorithm`	`Hash_Algorithm`	yes	The hash algorithm used for the checksum.
`value`	`string`	yes	The checksum value.

Example

json

{
  "algorithm": "sha256",
  "value": "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855"
}

Identity

Represents an identity that performed an action, such as capturing evidence or applying an override.

Field	Type	Required	Description
`identifier`	`string`	yes	The identifier value. Example: 'user@example.com', 'jdoe', 'automated-scanner-01'.
`type`	`"email"` \| `"username"` \| `"system"` \| `"simple"` \| `"other"`	yes	The type of identifier. Use 'email' for email addresses, 'username' for user accounts, 'system' for automated systems, 'simple' for basic string identifiers without additional classification, or 'other' for custom identity systems.
`description`	`string`	no	Optional description of the identity or identity system, particularly useful when type is 'other'.

Example

json

{
  "type": "email",
  "identifier": "admin@example.com"
}

Evidence

Supporting evidence for a finding or override, such as screenshots, code samples, log excerpts, or URLs.

Field	Type	Required	Description
`type`	`"screenshot"` \| `"code"` \| `"log"` \| `"url"` \| `"file"` \| `"other"`	yes	The type of evidence being provided.
`data`	`string`	yes	The evidence content. For screenshots/files: base64-encoded data or URL. For code/logs: the raw text. For URLs: the URL string.
`description`	`string`	no	Human-readable description of what this evidence shows.
`mimeType`	`string`	no	MIME type of the evidence. Example: 'image/png', 'text/plain', 'application/json'.
`encoding`	`string`	no	Encoding used for the data. Example: 'base64', 'utf-8'.
`size`	`number`	no	Size of the evidence data in bytes.
`capturedAt`	`string` (date-time)	no	Timestamp when this evidence was captured. ISO 8601 format.
`capturedBy`	`Identity`	no	Identity of who or what captured this evidence.

Example

json

{
  "type": "screenshot",
  "data": "iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAADUlEQVR42mNk+M9QDwADhgGAWjR9awAAAABJRU5ErkJggg==",
  "description": "Screenshot showing firewall configuration with required ports blocked",
  "mimeType": "image/png",
  "encoding": "base64",
  "size": 95,
  "capturedAt": "2025-12-14T10:30:00Z",
  "capturedBy": {
    "identifier": "security-auditor@example.com",
    "type": "email"
  }
}

Remediation

Reference to automated remediation resources for implementing security controls. Points to external automation content like Ansible playbooks, Terraform scripts, or vendor-provided remediation tools.

Field	Type	Required	Description
`uri`	`string` (uri)	yes	URI pointing to automated remediation resources (Ansible playbooks, Terraform scripts, etc.). Examples: GitHub repository, DISA STIG Supplemental Automation Content, vendor-provided scripts.
`checksum`	`Checksum`	no	Optional cryptographic checksum for verifying the integrity of remediation resources fetched from the URI. Recommended for security when referencing external automation scripts.

Example

json

{
  "uri": "https://github.com/ansible-lockdown/RHEL9-STIG/tree/main/tasks"
}

Verification_Method

Verification method containing the public key needed to verify a digital signature. Supports multiple key formats including JWK (for RSA, EC), PEM, and Base58.

Field	Type	Required	Description
`type`	`string`	yes	The type of verification method. Example: 'JsonWebKey2020', 'RsaVerificationKey2018', 'Ed25519VerificationKey2020'.
`controller`	`string`	yes	The entity that controls this verification method. Can be a DID, URI, or other identifier.
`publicKeyJwk`	Map<string, any>	no	Public key in JSON Web Key format.
`publicKeyPem`	`string`	no	Public key in PEM format. Example: '-----BEGIN PUBLIC KEY-----...-----END PUBLIC KEY-----'.
`publicKeyBase58`	`string`	no	Public key in Base58 format, commonly used with Ed25519 keys.

Milestone

A milestone or task within a POA&M remediation plan.

Field	Type	Required	Description
`description`	`string`	yes	Description of this milestone or task.
`estimatedCompletion`	`string` (date-time)	yes	Estimated completion date. ISO 8601 format.
`status`	`"pending"` \| `"inProgress"` \| `"completed"`	yes	Current status of this milestone.
`completedAt`	`string` (date-time)	no	Actual completion timestamp. ISO 8601 format.
`completedBy`	`Identity`	no	Identity of who completed this milestone.

Signature

A digital signature following W3C Data Integrity Proofs pattern. Supports hardware security tokens (PKCS#11/PKCS#12), Yubikeys, GPG keys, passkeys, and other cryptographic signing methods via JWK, PEM, or Base58 key formats.

Field	Type	Required	Description
`type`	`string`	yes	The signature suite type. Example: 'JsonWebSignature2020', 'RsaSignature2018', 'Ed25519Signature2020'.
`created`	`string` (date-time)	yes	When the signature was created. ISO 8601 format.
`creator`	`Identity`	yes	The identity that created this signature.
`signatureValue`	`string`	yes	The base64-encoded or base58-encoded signature value.
`proofPurpose`	`string`	yes	The purpose of this signature. Example: 'attestation', 'authentication', 'assertionMethod'.
`verificationMethod`	`Verification_Method`	yes	The verification method containing the public key for signature verification.
`nonce`	`string`	no	Random value to prevent replay attacks.
`challenge`	`string`	no	Challenge value from the verifier, used in challenge-response authentication.
`domain`	`string`	no	Domain restriction for the signature, prevents cross-domain replay attacks.

Example

json

{
  "type": "JsonWebSignature2020",
  "created": "2025-12-14T10:00:00Z",
  "creator": {
    "identifier": "security-team@example.com",
    "type": "email"
  },
  "signatureValue": "eyJhbGciOiJSUzI1NiIsImI2NCI6ZmFsc2UsImNyaXQiOlsiYjY0Il19..MEYCIQDvKbtLRhWAa",
  "proofPurpose": "attestation",
  "verificationMethod": {
    "type": "JsonWebKey2020",
    "controller": "did:example:123456789abcdefghi",
    "publicKeyJwk": {
      "kty": "RSA",
      "n": "0vx7agoebGcQSuuPiLJXZptN9nndrQmbXEps2aiAFbWhM78LhWx4cbbfAAtV",
      "e": "AQAB"
    }
  }
}

Baseline_Metadata

Shared metadata fields for baselines. Used in both standalone baseline documents and evaluated baseline results.

Field	Type	Required	Description
`name`	`string`	no	The name - must be unique.
`title`	`string`	no	The title - should be human readable.
`maintainer`	`string`	no	The maintainer(s).
`copyright`	`string`	no	The copyright holder(s).
`copyrightEmail`	`string`	no	The email address or other contact information of the copyright holder(s).
`license`	`string`	no	The copyright license. Example: 'Apache-2.0'.
`summary`	`string`	no	The summary. Example: the Security Technical Implementation Guide (STIG) header.
`version`	`string`	no	The version of the baseline.
`supports`	`Supported_Platform`[]	no	The set of supported platform targets.
`status`	`string`	no	The status. Example: 'loaded'.
`labels`	Map<string, `string`>	no	Optional key-value labels for flexible grouping. Well-known keys: system, component, environment, region, team. Values must be strings.

Example

json

{
  "name": "rhel-9-stig-baseline",
  "title": "Red Hat Enterprise Linux 9 STIG Baseline",
  "maintainer": "MITRE SAF Team",
  "copyright": "The MITRE Corporation",
  "copyrightEmail": "saf@mitre.org",
  "license": "Apache-2.0",
  "summary": "InSpec baseline for RHEL 9 STIG compliance",
  "version": "1.0.0",
  "supports": [
    {
      "platformName": "redhat",
      "platformFamily": "redhat",
      "release": "9"
    }
  ],
  "status": "loaded"
}

Requirement_Core

Core requirement fields shared between baseline requirements and evaluated requirements. Contains the fundamental requirement definition without assessment results.

Field	Type	Required	Description
`id`	`string`	no	The requirement identifier. Example: 'SV-238196'.
`title`	`string`	no	The title - is nullable.
`descriptions`	`object`[]	no	Array of labeled descriptions. At least one description with label 'default' must be present. Convention: place default description first. Common labels: 'default', 'check', 'fix', 'rationale'.
`impact`	`number`	no	The impactfulness or severity (0.0 to 1.0).
`refs`	`Reference`[]	no	The set of references to external documents.
`tags`	Map<string, any>	no	A set of tags - usually metadata like CCI, STIG ID, severity.
`code`	`string`	no	The raw source code of the requirement. Set to null for manual-only requirements or requirements not yet implemented. Note that if this is an overlay, it does not include the underlying source code.
`sourceLocation`	`Source_Location`	no	The explicit location of the requirement within the source code.

Example

json

{
  "id": "SV-238196",
  "title": "The Ubuntu operating system must enforce password complexity",
  "impact": 0.5,
  "tags": {
    "nist": [
      "IA-5"
    ],
    "severity": "medium",
    "cci": [
      "CCI-000192"
    ]
  },
  "refs": [
    {
      "url": "https://public.cyber.mil/stigs/"
    }
  ],
  "descriptions": [
    {
      "label": "default",
      "data": "Use of a complex password helps to increase the time and resources required to compromise the password."
    },
    {
      "label": "check",
      "data": "Verify the value of 'minlen' in /etc/security/pwquality.conf."
    }
  ]
}

Severity

Severity rating for a requirement. Typically derived from the numeric impact score.

Cloud_Provider

Cloud service provider identifier.

component/v3.1.0

Base_Component

Base properties shared by all component types. Extends the Target concept with stable identity, external references, and SBOM embedding.

Field	Type	Required	Description
`type`	`string`	yes	Component type discriminator. Same values as Target types.
`name`	`string`	yes	Human-readable name for this component.
`componentId`	`string` (uuid)	no	Stable UUID (RFC 4122) for this component. Required in hdf-system documents, optional in hdf-results. Enables cross-document correlation, diffing, and data flow references.
`description`	`string`	no	Description of this component's role or purpose.
`owner`	`Identity`	no	Team or individual responsible for this component. Enables per-component ownership when different teams manage different parts of a system.
`externalIds`	Map<string, `string`>	no	Map of external identifier scheme to value. Well-known schemes: aws (instance ID), azure (resource ID), cmdb (asset ID), emass (system ID), cve (CVE ID). Custom schemes are allowed.
`labels`	Map<string, `string`>	no	Optional key-value labels for flexible grouping. Well-known keys: system, component, environment, region, team. Values must be strings.
`sbom`	any	no	Embedded CycloneDX or SPDX SBOM document representing this component's software inventory. The sbomFormat field determines which format constraints apply.
`sbomRef`	`string` (uri-reference)	no	URI reference to an external CycloneDX or SPDX SBOM document for this component. May be a relative path, absolute URI, or fragment identifier.
`sbomFormat`	`"cyclonedx"` \| `"spdx"`	no	Format of the SBOM (embedded or referenced). Required when sbom or sbomRef is present.
`baselineRefs`	`string`[]	no	Names of baselines that apply to this component.
`inputOverrides`	`Input_Override`[]	no	System-specific overrides for baseline input values.
`targetSelector`	`Target_Selector`	no	Label selector to match targets belonging to this component during migration. Targets with matching labels are automatically included.

Component

A system component. Uses discriminated union pattern with 'type' field as discriminator. Superset of Target with identity, external IDs, and SBOM support.

Host_Component

A physical or virtual server, workstation, or network device.

Field	Type	Required	Description
`type`	`"host"`	no
`fqdn`	`string` (hostname)	no	Fully qualified domain name.
`ipAddress`	`string` (ipv4) \| `string` (ipv6)	no	IP address of the host.
`macAddress`	`string`	no	MAC address in colon-separated hexadecimal format.
`osName`	`string`	no	Operating system name.
`osVersion`	`string`	no	Operating system version.

Example

json

{
  "type": "host",
  "name": "web-server-prod-01",
  "componentId": "a1b2c3d4-e5f6-4a7b-8c9d-0e1f2a3b4c5d",
  "fqdn": "web01.prod.example.com",
  "ipAddress": "10.0.1.50",
  "osName": "Ubuntu",
  "osVersion": "22.04 LTS",
  "externalIds": {
    "cmdb": "ASSET-12345",
    "aws": "i-0abc123def456789"
  }
}

Container_Image_Component

A static container image (not running).

Field	Type	Required	Description
`type`	`"containerImage"`	no
`imageId`	`string`	no	Container image ID.
`registry`	`string`	no	Container registry. Example: 'docker.io'.
`repository`	`string`	no	Repository name. Example: 'library/nginx'.
`tag`	`string`	no	Image tag. Example: '1.25'.
`digest`	`string`	no	Image digest for immutable reference.

Container_Instance_Component

A running container instance.

Field	Type	Required	Description
`type`	`"containerInstance"`	no
`containerId`	`string`	no	Running container ID.
`image`	`string`	no	Image the container was started from.
`runtime`	`string`	no	Container runtime. Example: 'docker', 'containerd', 'cri-o'.

Container_Platform_Component

A container orchestration platform (Kubernetes, OpenShift, ECS, etc.).

Field	Type	Required	Description
`type`	`"containerPlatform"`	no
`platformType`	`string`	no	Platform type. Example: 'kubernetes', 'openshift', 'ecs', 'docker-swarm'.
`clusterName`	`string`	no	Cluster name.
`namespace`	`string`	no	Namespace within the cluster, if applicable.
`version`	`string`	no	Platform version.

Cloud_Account_Component

A cloud provider account (AWS account, Azure subscription, GCP project).

Field	Type	Required	Description
`type`	`"cloudAccount"`	no
`provider`	`Cloud_Provider`	no	Cloud provider.
`accountId`	`string`	no	Cloud account identifier.
`region`	`string`	no	Cloud region, if applicable.

Example

json

{
  "type": "cloudAccount",
  "name": "Production AWS Account",
  "componentId": "f1e2d3c4-b5a6-4978-8069-1a2b3c4d5e6f",
  "provider": "aws",
  "accountId": "123456789012",
  "region": "us-east-1"
}

Cloud_Resource_Component

A specific cloud resource (EC2 instance, S3 bucket, Azure VM, etc.).

Field	Type	Required	Description
`type`	`"cloudResource"`	no
`provider`	`Cloud_Provider`	no	Cloud provider.
`resourceType`	`string`	no	Type of cloud resource. Example: 'ec2:instance', 's3:bucket'.
`resourceId`	`string`	no	Provider-specific resource identifier.
`arn`	`string`	no	Amazon Resource Name (AWS only).
`region`	`string`	no	Cloud region where the resource resides.

Repository_Component

A code repository (for SAST tools).

Field	Type	Required	Description
`type`	`"repository"`	no
`url`	`string` (uri)	no	Repository URL.
`branch`	`string`	no	Branch that was scanned.
`commit`	`string`	no	Commit SHA that was scanned.

Application_Component

A running application or API (for DAST tools).

Field	Type	Required	Description
`type`	`"application"`	no
`url`	`string` (uri)	no	Application URL (for DAST tools).
`version`	`string`	no	Application version.
`environment`	`string`	no	Environment. Example: 'production', 'staging', 'development'.

Artifact_Component

A software artifact or dependency (for SCA tools).

Field	Type	Required	Description
`type`	`"artifact"`	no
`packageManager`	`string`	no	Package manager. Example: 'npm', 'maven', 'pip', 'nuget'.
`packageName`	`string`	no	Package name.
`version`	`string`	no	Package version.
`checksum`	`string`	no	Package checksum for verification.

Network_Component

A network segment or network device.

Field	Type	Required	Description
`type`	`"network"`	no
`cidr`	`string`	no	Network CIDR block.
`gateway`	`string`	no	Network gateway address.

Database_Component

A database instance.

Field	Type	Required	Description
`type`	`"database"`	no
`engine`	`string`	no	Database engine. Example: 'postgresql', 'mysql', 'oracle', 'mssql'.
`version`	`string`	no	Database version.
`host`	`string`	no	Database host.
`port`	`integer`	no	Database port.

data-flow/v3.1.0

Cross_System_Reference

Reference to a component in a different system document, enabling cross-boundary data flow modeling.

Field	Type	Required	Description
`systemRef`	`string` (uri-reference)	yes	URI reference to the hdf-system document containing the target component. May be a relative path, absolute URI, or fragment identifier.
`componentId`	`string` (uuid)	yes	UUID of the component in the referenced system.

External_Endpoint

An endpoint outside all modeled systems (e.g., a third-party API, public internet, or partner system not represented in HDF).

Field	Type	Required	Description
`external`	`"true"`	yes	Must be true. Discriminator indicating this endpoint is outside all modeled systems.
`description`	`string`	yes	Human-readable description of the external endpoint. Example: 'Third-party payment gateway (Stripe API)'.

Data_Flow_Endpoint

A data flow endpoint: either a local component (UUID), a component in another system (cross-system reference), or an external endpoint outside all modeled systems.

Data_Flow

A data flow between two endpoints. The 'from' endpoint is always a local component; the 'to' endpoint can be local, cross-system, or external. Use 'direction' to indicate whether data flows one-way or both ways.

Field	Type	Required	Description
`from`	`string` (uuid)	yes	UUID of the local component that is one end of this data flow. Always references a component in the current system document.
`to`	`Data_Flow_Endpoint`	yes	The other end of this data flow. Can be a local component (UUID), a cross-system component reference, or an external endpoint.
`protocol`	`string`	no	Communication protocol. Examples: 'http', 'https', 'grpc', 'ssh', 'jdbc', 'k8s-api', 'socket', 'sftp'.
`port`	`integer`	no	Network port number.
`direction`	`"unidirectional"` \| `"bidirectional"`	no	Data flow direction. 'unidirectional' means data flows from→to only. 'bidirectional' means data flows in both directions (e.g., request/response).
`description`	`string`	no	Human-readable description of this data flow's purpose and the data exchanged.
`authentication`	`string`	no	Authentication mechanism used for this connection. Examples: 'mTLS', 'OAuth2', 'API key', 'SAML', 'Kerberos'.

Example

json

{
  "from": "f47ac10b-58cc-4372-a567-0e02b2c3d479",
  "to": "a1b2c3d4-e5f6-7890-abcd-ef1234567890",
  "protocol": "https",
  "port": 443,
  "direction": "bidirectional",
  "description": "REST API calls from WebTier to API Gateway",
  "authentication": "mTLS"
}

extensions/v3.1.0

Status_Override

An intentional change to a requirement's compliance status and/or impact score. At least one of status or impact must be set. Overrides change the effectiveStatus or impact of the requirement. All overrides must have an expiration date to enforce periodic review.

Field	Type	Required	Description
`type`	`Override_Type`	yes	The type of override applied to this requirement.
`status`	`Result_Status`	no	The new status this override sets for the requirement. Optional when only impact is being overridden.
`impact`	`Impact_Override`	no	Override to the requirement's impact score. At least one of status or impact must be set.
`reason`	`string`	yes	Explanation for why this override was applied.
`appliedBy`	`Identity`	yes	Identity of who applied this override. For simple cases, use type 'simple' with just an identifier.
`appliedAt`	`string` (date-time)	yes	Timestamp when this override was applied. ISO 8601 format.
`expiresAt`	`string` (date-time)	yes	Timestamp when this override expires and must be reviewed/renewed. REQUIRED - no permanent overrides allowed. ISO 8601 format.
`signature`	`Signature`	no	Optional digital signature for enhanced trust and non-repudiation. Supports hardware security tokens (PKCS#11/PKCS#12), Yubikeys, GPG keys, passkeys, and other signing methods.
`evidence`	`Evidence`[]	no	Supporting evidence for this override, such as screenshots demonstrating manual verification for attestations.
`previousChecksum`	`Checksum`	no	SHA-256 checksum of the previous amendment in chronological order. Creates a tamper-evident chain of amendments (similar to blockchain). Null for the first amendment on a requirement.

Example

json

{
  "type": "waiver",
  "status": "notApplicable",
  "reason": "This control does not apply to containerized environments as the application runs in ephemeral containers without persistent storage",
  "appliedBy": {
    "identifier": "security-team@example.com",
    "type": "email"
  },
  "appliedAt": "2025-12-01T10:00:00Z",
  "expiresAt": "2026-12-01T00:00:00Z"
}

POAM

Plan of Action and Milestones for tracking remediation, mitigation, or risk acceptance. POAMs do NOT change the effectiveStatus - the requirement remains in its current state while the POA&M tracks remediation efforts.

Field	Type	Required	Description
`type`	`"remediation"` \| `"mitigation"` \| `"riskAcceptance"` \| `"vendorDependency"`	yes	The type of POA&M. 'remediation' fixes root cause. 'mitigation' reduces risk via compensating controls. 'riskAcceptance' documents decision to accept risk. 'vendorDependency' tracks a fix that depends on a vendor releasing a patch or update.
`explanation`	`string`	yes	Detailed explanation of the plan, including what actions will be taken.
`appliedBy`	`Identity`	yes	Identity of who created this POA&M. For simple cases, use type 'simple' with just an identifier.
`appliedAt`	`string` (date-time)	yes	Timestamp when this POA&M was created. ISO 8601 format.
`expiresAt`	`string` (date-time)	no	Optional expiration date for this POA&M requiring review/renewal. ISO 8601 format.
`milestones`	`Milestone`[]	no	Optional array of milestones tracking progress toward completion.
`signature`	`Signature`	no	Optional digital signature for enhanced trust and non-repudiation.
`evidence`	`Evidence`[]	no	Supporting evidence for this POA&M, such as documentation of compensating controls or mitigation implementation.
`previousChecksum`	`Checksum`	no	SHA-256 checksum of the previous amendment in chronological order. Creates a tamper-evident chain of amendments (similar to blockchain). Null for the first amendment on a requirement.

Example

json

{
  "type": "remediation",
  "explanation": "Upgrade OpenSSL to version 3.0.x to address CVE-2024-XXXXX vulnerability. Root cause: outdated dependency version in base image.",
  "appliedBy": {
    "identifier": "devops-team@example.com",
    "type": "email"
  },
  "appliedAt": "2025-12-01T09:00:00Z",
  "milestones": [
    {
      "description": "Update base Docker image to use OpenSSL 3.0.x",
      "estimatedCompletion": "2025-12-15T00:00:00Z",
      "status": "completed",
      "completedAt": "2025-12-10T16:30:00Z",
      "completedBy": {
        "identifier": "alice.smith",
        "type": "username"
      }
    },
    {
      "description": "Deploy updated image to production",
      "estimatedCompletion": "2025-12-20T00:00:00Z",
      "status": "inProgress"
    },
    {
      "description": "Verify vulnerability no longer present via security scan",
      "estimatedCompletion": "2025-12-22T00:00:00Z",
      "status": "pending"
    }
  ]
}

Generator

Information about the tool that generated this HDF file.

Field	Type	Required	Description
`name`	`string`	yes	The name of the software that produced this HDF file. Example: 'gosec-to-hdf'.
`version`	`string`	yes	The version of the tool. Example: '5.22.3'.

Tool

The security tool that produced the assessment data represented in this HDF file. Aligns with SARIF, OSCAL, and CycloneDX terminology.

Field	Type	Required	Description
`name`	`string`	no	The name of the security tool that produced the data. Examples: 'gosec', 'Semgrep', 'OpenSCAP', 'AWS Config', 'Nessus'. Omit if the tool cannot be identified.
`version`	`string`	no	Version of the source tool, if available in the tool's output. Example: '5.22.3'.
`format`	`string`	no	The file format, if it is a recognized named format shared by multiple tools. Examples: 'SARIF', 'XCCDF'. Omit for tool-specific formats where the tool name already implies the format (Nessus XML, gosec JSON).

Integrity

Cryptographic integrity information for verifying the HDF file has not been tampered with. If algorithm is provided, checksum must also be provided, and vice versa.

Field	Type	Required	Description
`algorithm`	`Hash_Algorithm`	no	The hash algorithm used for the checksum.
`checksum`	`string`	no	The checksum value.
`signature`	`string`	no	Optional cryptographic signature.
`signedBy`	`string`	no	Identifier of who signed this file.

Example

json

{
  "algorithm": "sha256",
  "checksum": "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855"
}

result/v3.1.0

Result_Status

The status of an individual test result. 'notApplicable' indicates the requirement does not apply to the target. 'notReviewed' indicates the requirement was not assessed (e.g., requires manual verification).

Requirement_Result

A test within a requirement and its results and findings such as how long it took to run.

Field	Type	Required	Description
`status`	`Result_Status`	yes	The status of this test within the requirement. Example: 'failed'.
`codeDesc`	`string`	yes	A description of this test. Example: 'limits.conf * is expected to include ["hard", "maxlogins", "10"]'.
`runTime`	`number`	no	The execution time in seconds for the test.
`startTime`	`string` (date-time)	yes	The time at which the test started.
`resource`	`string`	no	The resource used in the test. Example: 'file', 'command', 'service'.
`resourceId`	`string`	no	The unique identifier of the resource. Example: '/etc/passwd'.
`message`	`string`	no	An explanation of the test result. Typically provided for failed tests, errors, or to explain why a test was not applicable or not reviewed.
`exception`	`string`	no	The type of exception if an exception was thrown.
`backtrace`	`string`[]	no	The stacktrace/backtrace of the exception if one occurred.

Example

json

{
  "status": "passed",
  "codeDesc": "File /etc/ssh/sshd_config content is expected to match /Protocol\\s+2/",
  "startTime": "2025-06-15T10:30:00Z",
  "runTime": 0.015
}

Requirement_Description

A labeled description for a requirement, such as fix text or check instructions.

Field	Type	Required	Description
`label`	`string`	yes	The type of description. Examples: 'fix', 'check', 'rationale'.
`data`	`string`	yes	The text of the description.

Example

json

{
  "label": "default",
  "data": "Verify the SSH daemon is configured to only use FIPS-validated key exchange algorithms."
}

system/v3.1.0

Authorization_Status

Authorization to Operate (ATO) status for the system.

Categorization_Level

FIPS 199 security categorization level (impact level).

Input_Override

An override of a baseline input value for a specific component. Enables system-specific tailoring of baseline parameters.

Field	Type	Required	Description
`baselineRef`	`string`	no	Name of the baseline this override applies to. If omitted, applies to all baselines that define this input.
`inputName`	`string`	yes	Name of the input being overridden. Must match an Input.name in the referenced baseline.
`value`	any	yes	The overridden value. Should match the type of the original input.
`justification`	`string`	no	Rationale for why this override is needed.
`approvedBy`	`Identity`	no	Identity of the person or system that approved this override.

Target_Selector

A label selector that matches targets by label key-value pairs. All specified labels must match (AND logic). Example: { "labels.component": "WebTier" } matches targets with labels.component = "WebTier".

Control_Designation

Declares a control's designation within a system — whether it is common (provided by another component or system), system-specific (implemented locally), or hybrid (shared responsibility). Maps to NIST SP 800-53 Appendix C control designations and OSCAL SSP by-component provided/inherited semantics.

Field	Type	Required	Description
`controlId`	`string`	yes	The control identifier (e.g., 'SC-7', 'AC-2 (1)'). Must match a NIST tag in a baseline requirement's tags.
`designation`	`"common"` \| `"system-specific"` \| `"hybrid"`	yes	NIST SP 800-53 control designation. 'common': fully provided by another component or system. 'system-specific': implemented by the inheriting component(s) only. 'hybrid': shared responsibility between provider and inheritor.
`providedBy`	`string` (uuid)	no	componentId of a local component that provides this control. Omit when the provider is an external system.
`systemRef`	`string` (uri-reference)	no	Reference to another hdf-system document whose component provides this control. Use when the provider is in a different system. Omit when the provider is local.
`inheritedBy`	`string` (uuid)[]	no	componentIds that inherit this control. If omitted, all components in the system inherit it.
`description`	`string`	yes	Justification for this designation — who provides the control, why it's inherited, and any relevant authorization references.

Example

json

{
  "controlId": "IA-2",
  "designation": "common",
  "providedBy": "aaaaaaaa-bbbb-cccc-dddd-eeeeeeeeeeee",
  "inheritedBy": [
    "11111111-2222-3333-4444-555555555555"
  ],
  "description": "User identification and authentication provided by Keycloak SSO via SAML 2.0."
}

HDF System ​

Properties ​

Example ​

Embedded Primitives ​

amendments/v3.1.0 ​

Override_Type ​

Impact_Override ​

Standalone_Override ​

common/v3.1.0 ​

Hash_Algorithm ​

Requirement_Group ​

Dependency ​

Reference ​

Source_Location ​

Supported_Platform ​

Checksum ​

Identity ​

Evidence ​

Remediation ​

Verification_Method ​

Milestone ​

Signature ​

Baseline_Metadata ​

Requirement_Core ​

Severity ​

Cloud_Provider ​

component/v3.1.0 ​

Base_Component ​

Component ​

Host_Component ​

Container_Image_Component ​

Container_Instance_Component ​

Container_Platform_Component ​

Cloud_Account_Component ​

Cloud_Resource_Component ​

Repository_Component ​

Application_Component ​

Artifact_Component ​

Network_Component ​

Database_Component ​

data-flow/v3.1.0 ​

Cross_System_Reference ​

External_Endpoint ​

Data_Flow_Endpoint ​

Data_Flow ​

extensions/v3.1.0 ​

Status_Override ​

POAM ​

Generator ​

Tool ​

Integrity ​

result/v3.1.0 ​

Result_Status ​

Requirement_Result ​

Requirement_Description ​

system/v3.1.0 ​

Authorization_Status ​

Categorization_Level ​

Input_Override ​

Target_Selector ​

Control_Designation ​

HDF System

Properties

Example

Embedded Primitives

amendments/v3.1.0

Override_Type

Impact_Override

Standalone_Override

common/v3.1.0

Hash_Algorithm

Requirement_Group

Dependency

Reference

Source_Location

Supported_Platform

Checksum

Identity

Evidence

Remediation

Verification_Method

Milestone

Signature

Baseline_Metadata

Requirement_Core

Severity

Cloud_Provider

component/v3.1.0

Base_Component

Component

Host_Component

Container_Image_Component

Container_Instance_Component

Container_Platform_Component

Cloud_Account_Component

Cloud_Resource_Component

Repository_Component

Application_Component

Artifact_Component

Network_Component

Database_Component

data-flow/v3.1.0

Cross_System_Reference

External_Endpoint

Data_Flow_Endpoint

Data_Flow

extensions/v3.1.0

Status_Override

POAM

Generator

Tool

Integrity

result/v3.1.0

Result_Status

Requirement_Result

Requirement_Description

system/v3.1.0

Authorization_Status

Categorization_Level

Input_Override

Target_Selector

Control_Designation