Configure Container Scan

Configure Container Scan

Add a container image scanning step to an existing Harness pipeline using the native HarnessSCA STO scanner.

Instructions

Step 1: Establish Scope and Pipeline Context

Ask for org, project, and pipeline identifier if not already known. This skill only works with existing pipelines.

Call MCP tool: harness_get
Parameters:
  resource_type: "pipeline"
  resource_id: ""
  org_id: ""
  project_id: ""

Step 2: Analyze Pipeline Structure

Parse the pipeline YAML to identify:

• All stages and their types (CI, SecurityTests, Deployment, Approval)
• Whether a SecurityTests stage already exists
• Existing steps in each stage

Present the structure to the user:

Pipeline: 

Stage 1:  (type: )
  - Step 1:  (type: )
  ...

Ask the user where they want the scanner step added:

Present the available insertion points:

• Any existing CI stage (scanner step is added directly into that stage's execution.steps)
• Any existing SecurityTests stage (scanner step is added into that stage's execution.steps)
• A new SecurityTests stage (appended to the pipeline if no suitable stage exists or user prefers isolation)

Recommendation guidance:

• Adding into an existing CI stage — simpler, no extra infrastructure needed, scan runs as part of the build
• Adding a new SecurityTests stage — isolated, runs independently, useful when scanning images built elsewhere or from a registry

If the user doesn't specify, default to adding inside the existing CI stage if one exists.

Step 3: Recommend Scanner Type

Present the available container image scanners supported in Harness STO:

Available Container Scanners:

• Harness SCA (default — native Harness container scanner, zero config)
• Aqua Trivy (open-source, broad OS and library coverage)
• Grype (open-source by Anchore, fast and accurate)
• Snyk (commercial, developer-friendly with fix advice)
• Prisma Cloud (commercial, enterprise runtime + image scanning)
• Anchore Enterprise (commercial, policy-based enforcement)
• Black Duck (commercial, license compliance + vulnerabilities)
• Wiz (commercial, cloud-native security)

Default recommendation: Use Harness SCA — native, no additional credentials required, and integrates directly with Harness STO results.

Ask the user which scanner they prefer. If they don't specify, use Harness SCA as the default.

Step type mapping and scanner product auth requirements:

| Scanner | type field | Product auth needed? | Auth fields | |---------|-------------|----------------------|-------------| | Harness SCA | HarnessSCA | No | — | | Aqua Trivy | AquaTrivy | No | — | | Grype | Grype | No | — | | Snyk | Snyk | Yes | access_token (Snyk API token) | | Prisma Cloud | PrismaCloud | Yes | access_id (Access Key), access_token (Secret Key) | | Anchore Enterprise | AnchoreEnterprise | Yes | access_id (username), access_token (password/API key) | | Black Duck | BlackDuck | Yes | access_token (Hub API token) | | Wiz | Wiz | Yes | access_id (Client ID), access_token (Client Secret) |

If the user picks a commercial scanner (Snyk, Prisma Cloud, Anchore Enterprise, Black Duck, Wiz):

1. Inform the user that this scanner requires product-level authentication credentials
2. Ask for the required secret references from the table above — these must already exist as Harness secrets
3. Format them as ")>
4. These go into the auth block of the step spec — separate from the registry image credentials

Example prompt to user: > "Snyk requires an API token. Please provide the Harness secret identifier for your Snyk API token (e.g., snyk_api_token). I'll reference it as ``."

If the secret doesn't exist yet, suggest creating it first via /create-secret before proceeding.

Step 4: Collect Container Image Details (skip for Prisma Cloud / Wiz — they pull from registry via connector)

Ask the user which registry type their image is in, then collect the fields for that type:

---

Option A — Harness Registry

The image is stored in the Harness internal container registry.

| Field | Required | Description | |-------|----------|-------------| | Registry | Yes | Harness registry connector ref (e.g., account.account-level-test) | | Image Path | Yes | e.g., harness/todolist-sample — maps to image_path in YAML |

YAML:

      image:
        type: harness
        registry: 
        image_path: 

---

Option B — Third-Party Registry (Docker Hub, ECR, GCR, ACR, JFrog, etc.)

| Field | Required | Description | |-------|----------|-------------| | Type | Yes | Registry protocol — almost always docker_v2 | | Domain | No | Defaults to docker.io. For ECR: 123456789.dkr.ecr.us-east-1.amazonaws.com, for GCR: gcr.io | | Name | Yes | Image name, e.g., harness/todolist-sample or myorg/myapp | | Tag / Digest | Yes | e.g., latest, 123, or sha256:1234567890abcdef... | | Access Id | No | Secret ref for private registry username/access key, e.g., ` | | Access Token | No | Secret ref for private registry password/token, e.g., ` |

YAML:

      image:
        type: docker_v2
        domain:               # omit if Docker Hub (docker.io)
        name: 
        tag: 
        access_id:      # omit if public image
        access_token:   # omit if public image

---

Option C — Local (image built in this stage)

The image was built earlier in the same pipeline stage and is available locally on the build node.

| Field | Required | Description | |-------|----------|-------------| | Name | Yes | Image name, e.g., harness/todolist-sample | | Tag / Digest | Yes | e.g., latest, 123, or sha256:1234567890abcdef... | | Domain | No | Defaults to docker.io |

YAML:

      image:
        type: local_image
        name: 
        tag: 
        domain:    # omit if not needed

---

Default: Third-Party → Docker Hub (docker_v2, domain docker.io) with latest tag if the user doesn't specify.

Step 4: Collect Infrastructure Details (if needed)

Only required when adding a new SecurityTests stage. If inserting into an existing CI or SecurityTests stage, skip this step — the stage already has infrastructure.

If a new SecurityTests stage is being created and infrastructure is not yet defined, ask for:

• Delegate connector (e.g., account.stoqadelegate)
• Namespace (e.g., harness-delegate)

Step 5: Generate the Scanner Step YAML

Use the step type from the scanner mapping in Step 3. Examples below.

For Harness SCA (default scanner):

- step:
    type: HarnessSCA
    name: Container_Scan
    identifier: Container_Scan
    spec:
      mode: orchestration
      config: default
      target:
        type: container
        detection: auto
      advanced:
        log:
          level: info
      resources:
        limits:
          memory: 2G
          cpu: 1000m
      privileged: true
      image:
        

Use the image block generated in Step 4 (Harness / Third-Party / Local). The rest of the step spec is identical regardless of registry type.

For Aqua Trivy (open-source):

- step:
    type: AquaTrivy
    name: Aqua_Trivy_Scan
    identifier: Aqua_Trivy_Scan
    spec:
      mode: orchestration
      config: default
      target:
        type: container
        detection: auto
      advanced:
        log:
          level: info
      privileged: true
      image:
        type: docker_v2
        name: 
        tag: 

For Grype (open-source):

- step:
    type: Grype
    name: Grype_Scan
    identifier: Grype_Scan
    spec:
      mode: orchestration
      config: default
      target:
        type: container
        detection: auto
      advanced:
        log:
          level: info
      privileged: true
      image:
        type: docker_v2
        name: 
        tag: 

For commercial scanners — add an auth block with scanner product credentials:

- step:
    type: Snyk                       # or PrismaCloud, AnchoreEnterprise, BlackDuck, Wiz
    name: Snyk_Container_Scan
    identifier: Snyk_Container_Scan
    spec:
      mode: orchestration
      config: default
      target:
        type: container
        detection: auto
      auth:
        access_id:      # omit if scanner only needs token
        access_token: 
      advanced:
        log:
          level: info
      privileged: true
      image:
        type: docker_v2
        name: 
        tag: 

Use the auth field names from the scanner product auth table in Step 3. Only include access_id if the scanner requires it (Snyk only needs access_token; Prisma Cloud, Anchore, and Wiz need both).

Step 6: Build the Updated Pipeline YAML

Scenario A — Adding to an existing CI stage:

Insert the step into spec.execution.steps of the chosen CI stage. The stage already has its own infrastructure and cloneCodebase: true. No changes needed to the stage itself — just append the step:

- step:
    type: HarnessSCA
    name: Container_Scan
    identifier: Container_Scan
    spec:
      mode: orchestration
      config: default
      target:
        type: container
        detection: auto
      advanced:
        log:
          level: info
      resources:
        limits:
          memory: 2G
          cpu: 1000m
      privileged: true
      image:
        type: docker_v2
        name: 
        tag: 

Scenario B — Adding to an existing SecurityTests stage:

Insert the step into spec.execution.steps of the existing stage. Ensure the stage has:

• cloneCodebase: false
• privileged: true on the step

Scenario C — No suitable stage exists, creating a new SecurityTests stage:

Append a new stage to the pipeline:

- stage:
    name: Container Scan
    identifier: Container_Scan_Stage
    type: SecurityTests
    spec:
      cloneCodebase: false
      infrastructure:
        type: KubernetesDirect
        spec:
          connectorRef: 
          namespace: 
          automountServiceAccountToken: true
          nodeSelector: {}
          os: Linux
      execution:
        steps:
          - step:
              type: HarnessSCA
              name: Container_Scan
              identifier: Container_Scan
              spec:
                mode: orchestration
                config: default
                target:
                  type: container
                  detection: auto
                advanced:
                  log:
                    level: info
                resources:
                  limits:
                    memory: 2G
                    cpu: 1000m
                privileged: true
                image:
                  type: docker_v2
                  name: 
                  tag: 

Step 7: Update Pipeline via MCP

Call MCP tool: harness_update
Parameters:
  resource_type: "pipeline"
  resource_id: ""
  org_id: ""
  project_id: ""
  body: { yamlPipeline: "" }

Step 8: Provide Summary and Next Steps

## Container Scan Configured

**Pipeline:** 
**Scanner:**  ()
**Stage:**  (SecurityTests)
**Image:** :
**Registry:** 

**Pipeline URL:** https://app.harness.io/ng/account//module/sto/orgs//projects//pipelines//pipeline-studio/

### Next Steps
1. Run the pipeline to verify the scan step executes successfully
2. View scan results in the Security Tests tab of the execution
3. Set failure thresholds using `failOnSeverity` (CRITICAL, HIGH, MEDIUM, LOW) in the step's Advanced tab
4. Configure exemptions for false positives via `/security-report` skill
5. Enforce pipeline gates on severity via `/create-policy` skill

Examples

Scan a public Docker Hub image

/create-container-scan
Add a container scan to my pipeline for the image johnkday/nodegoat:latest

Scan a private ECR image

/create-container-scan
Add container scanning to my deploy pipeline. The image is in ECR:
123456789.dkr.ecr.us-east-1.amazonaws.com/my-service:v2.1.0
Use our ECR credentials stored in secrets.

Add scan before deployment

/create-container-scan
I want to scan my Docker image myorg/api-server:latest before it gets deployed.
Add it to the existing SecurityTests stage in my backend-deploy pipeline.

Performance Notes

• Only works with existing pipelines — do not offer to create a new standalone pipeline
• Always ask the user which scanner they want — present the full list; default to Harness SCA if not specified
• HarnessSCA (and all other scanners) can be added to CI stages (inline with build) or SecurityTests stages (isolated) — ask the user, default to CI stage if one exists
• For commercial scanners (Snyk, Prisma Cloud, Anchore, Black Duck, Wiz), always ask for scanner product credentials (auth.access_id / auth.access_token) before generating YAML — these are different from registry credentials
• If required secrets don't exist yet, prompt the user to create them via /create-secret before proceeding
• auth block sits at the step spec level, separate from image credentials
• Always set privileged: true on the HarnessSCA step — it is required for container scanning
• Only ask for delegate infrastructure when creating a new SecurityTests stage — existing stages already have infrastructure
• Only set cloneCodebase: false on SecurityTests stages — CI stages already manage their own codebase setting
• Default to mode: orchestration and config: default unless the user specifies otherwise
• Set resource limits of memory: 2G and cpu: 1000m to avoid OOM failures during scan
• For ECR images, domain must include the full registry URL, not just the region

Troubleshooting

Pipeline Not Found

• Verify org_id and project_id are correct
• Confirm the pipeline exists with harness_list (resource_type: "pipeline")

Scan Step Fails with Permission Error

• Ensure privileged: true is set on the step spec
• Verify the delegate has Docker socket access in the namespace

Image Pull Failure

• For private registries, ensure image.access_id and image.access_token reference valid secrets
• For ECR, confirm the delegate has the correct IAM role to pull images
• For Docker Hub, check rate limits; supply credentials to avoid anonymous pull limits

Scanner Authentication Failure (commercial scanners)

• Verify auth.access_token (and auth.access_id where required) reference valid Harness secrets
• Confirm the secret identifiers match exactly — check with harness_get(resource_type="secret")
• For Snyk: only access_token is needed (API token), not access_id
• For Prisma Cloud / Wiz / Anchore: both access_id and access_token are required
• If secrets don't exist, create them first via /create-secret then re-run the skill

No Results in Security Tests Tab

• Confirm STO module is enabled for the account
• Check the execution logs for scanner errors
• Verify the image name and tag are correct and the image exists in the registry

Pipeline Update Validation Errors

• Verify YAML indentation (2 spaces throughout)
• Ensure step identifier matches pattern ^[a-zA-Z_][0-9a-zA-Z_]{0,127}$
• Confirm the SecurityTests stage has a valid infrastructure block with a working delegate connector

Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: harness
• Source: harness/harness-skills
• License: Apache-2.0
• Homepage: https://developer.harness.io/docs/platform/harness-ai/harness-skills/

Install and usage instructions live in the source repository linked above.