Securing Helm Chart Deployments

---
name: securing-helm-chart-deployments
description: Use when secure Helm chart deployments by validating chart integrity,
  scanning templates for misconfigurations, and enforcing security contexts in Kubernetes
  releases. Use when working with securing helm chart deployments.
domain: cybersecurity
subdomain: container-security
tags:
- helm
- kubernetes
- chart-security
- supply-chain
- configuration-security
- deployment
version: '1.0'
author: oyi77
license: Apache-2.0
nist_csf:
- PR.PS-01
- PR.IR-01
- ID.AM-08
- DE.CM-01
category: cybersecurity
---


# Securing Helm Chart Deployments

## Overview

Helm is the Kubernetes package manager. Securing Helm deployments requires validating chart provenance, scanning templates for security misconfigurations, enforcing pod security contexts, managing secrets securely, and controlling RBAC for Helm operations.


## When to Use
**Trigger phrases:**
- "securing helm chart deployments"
- "Secure Helm chart deployments by validating chart integrity, scanning templates "


- When deploying or configuring securing helm chart deployments capabilities in your environment
- When establishing security controls aligned to compliance requirements
- When building or improving security architecture for this domain
- When conducting security assessments that require this implementation

## Prerequisites

- Helm 3.12+ installed
- kubectl with cluster access
- GnuPG for chart signing/verification
- kubesec or checkov for template scanning

## Chart Provenance and Integrity

This section covers chart provenance and integrity for securing helm chart deployments.

- Ensure all prerequisites are met before proceeding
- Follow the documented workflow steps in sequence
- Record results and any anomalies encountered during this phase
### Sign a Helm Chart

```bash
# Generate GPG key for signing
gpg --full-generate-key

# Package and sign chart
helm package ./mychart --sign --key "helm-signing@example.com" --keyring ~/.gnupg/pubring.gpg

# Verify chart signature
helm verify mychart-0.1.0.tgz --keyring ~/.gnupg/pubring.gpg
```

### Verify Chart Before Install

```bash
# Verify chart from repository
helm pull myrepo/mychart --verify --keyring /path/to/keyring.gpg

# Check chart provenance file
cat mychart-0.1.0.tgz.prov
```

## Template Security Scanning

This section covers template security scanning for securing helm chart deployments.

- Ensure all prerequisites are met before proceeding
- Follow the documented workflow steps in sequence
- Record results and any anomalies encountered during this phase
### Render and Scan Templates

```bash
# Render templates without deploying
helm template myrelease ./mychart --values values-prod.yaml > rendered.yaml

# Scan with kubesec
kubesec scan rendered.yaml

# Scan with checkov
checkov -f rendered.yaml --framework kubernetes

# Scan with trivy
trivy config rendered.yaml

# Scan with kube-linter
kube-linter lint rendered.yaml
```

### Helm Lint for Misconfigurations

```bash
# Lint chart
helm lint ./mychart --values values-prod.yaml --strict

# Lint with debug output
helm lint ./mychart --debug
```

## Security Context Enforcement in values.yaml

```yaml
# values.yaml - Security hardened defaults
securityContext:
  runAsNonRoot: true
  runAsUser: 1000
  runAsGroup: 3000
  fsGroup: 2000
  readOnlyRootFilesystem: true
  allowPrivilegeEscalation: false
  capabilities:
    drop:
      - ALL

podSecurityContext:
  seccompProfile:
    type: RuntimeDefault

resources:
  limits:
    cpu: 500m
    memory: 512Mi
  requests:
    cpu: 100m
    memory: 128Mi

networkPolicy:
  enabled: true

serviceAccount:
  create: true
  automountServiceAccountToken: false

image:
  pullPolicy: Always
  # Use digest instead of tag for immutability
  # tag: "1.0.0"
  # digest: "sha256:abc123..."
```

### Template with Security Contexts

```yaml
# templates/deployment.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: {{ include "mychart.fullname" . }}
spec:
  template:
    spec:
      automountServiceAccountToken: {{ .Values.serviceAccount.automountServiceAccountToken }}
      securityContext:
        {{- toYaml .Values.podSecurityContext | nindent 8 }}
      containers:
        - name: {{ .Chart.Name }}
          securityContext:
            {{- toYaml .Values.securityContext | nindent 12 }}
          image: "{{ .Values.image.repository }}:{{ .Values.image.tag }}"
          resources:
            {{- toYaml .Values.resources | nindent 12 }}
```

## Secrets Management

This section covers secrets management for securing helm chart deployments.

- Ensure all prerequisites are met before proceeding
- Follow the documented workflow steps in sequence
- Record results and any anomalies encountered during this phase
### Use External Secrets (Not Helm Values)

```yaml
# templates/external-secret.yaml
apiVersion: external-secrets.io/v1beta1
kind: ExternalSecret
metadata:
  name: {{ include "mychart.fullname" . }}-secrets
spec:
  refreshInterval: 1h
  secretStoreRef:
    name: aws-secretsmanager
    kind: ClusterSecretStore
  target:
    name: {{ include "mychart.fullname" . }}-secrets
  data:
    - secretKey: db-password
      remoteRef:
        key: production/database
        property: password
```

### helm-secrets Plugin

```bash
# Install helm-secrets plugin
helm plugin install https://github.com/jkroepke/helm-secrets

# Encrypt values file
helm secrets encrypt values-secrets.yaml

# Deploy with encrypted secrets
helm secrets install myrelease ./mychart -f values.yaml -f values-secrets.yaml

# Decrypt for editing
helm secrets edit values-secrets.yaml
```

## RBAC for Helm Operations

```yaml
# helm-deployer-role.yaml
apiVersion: rbac.authorization.k8s.io/v1
kind: Role
metadata:
  name: helm-deployer
  namespace: production
rules:
  - apiGroups: ["", "apps", "batch", "networking.k8s.io"]
    resources: ["deployments", "services", "configmaps", "secrets", "ingresses", "jobs"]
    verbs: ["get", "list", "create", "update", "patch", "delete"]
  - apiGroups: [""]
    resources: ["pods", "pods/log"]
    verbs: ["get", "list"]

---
apiVersion: rbac.authorization.k8s.io/v1
kind: RoleBinding
metadata:
  name: helm-deployer-binding
  namespace: production
subjects:
  - kind: ServiceAccount
    name: helm-deployer
    namespace: production
roleRef:
  kind: Role
  name: helm-deployer
  apiGroup: rbac.authorization.k8s.io
```

## CI/CD Helm Security Pipeline

```yaml
# .github/workflows/helm-security.yaml
name: Helm Chart Security
on:
  pull_request:
    paths: ['charts/**']

jobs:
  lint-and-scan:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4

      - name: Helm lint
        run: helm lint ./charts/mychart --strict

      - name: Render templates
        run: helm template test ./charts/mychart -f charts/mychart/values.yaml > rendered.yaml

      - name: Scan with kube-linter
        uses: stackrox/kube-linter-action@v1
        with:
          directory: rendered.yaml

      - name: Scan with trivy
        uses: aquasecurity/trivy-action@master
        with:
          scan-type: config
          scan-ref: rendered.yaml

      - name: Scan with checkov
        uses: bridgecrewio/checkov-action@master
        with:
          file: rendered.yaml
          framework: kubernetes
```

## Best Practices

1. **Sign charts** with GPG and verify before installation
2. **Render and scan** templates before deploying to catch misconfigurations
3. **Enforce security contexts** in values.yaml defaults
4. **Never store secrets** in Helm values - use external secrets or helm-secrets plugin
5. **Use image digests** instead of tags for immutable references
6. **Restrict Helm RBAC** to least privilege per namespace
7. **Pin chart versions** in requirements - never use `latest`
8. **Lint strictly** in CI with `--strict` flag
9. **Review third-party charts** before deploying to production
10. **Use Helm test hooks** to validate deployments post-install
## When NOT to Use

- You need to test security controls (use performing-* skills)
- Task is about detecting bypasses (use detecting-* skills)
- You need to analyze security events (use analyzing-* skills)
- Task is about building security tools (use building-* skills)
- You don't have admin access to the system
- Task requires compliance certification (use auditing-* skills)


## Red Flags

- Performing actions without explicit written authorization from the asset owner
- Testing against production systems without a defined scope and rules of engagement
- Sharing sensitive findings or credentials in unencrypted communications
- Failing to properly scope and contain the assessment before starting
## Verification

- All steps executed successfully against a test environment before production use
- Output documented with screenshots or logs demonstrating expected behavior
- Results validated against known-good baselines or reference implementations
- Documentation complete enough for another analyst to reproduce findings

## Process

1. Analyze the task requirements
2. Apply domain expertise
3. Verify output quality

## Anti-Rationalization Table

| Rationalization | Reality |
|---|---|
| "We are too small to be targeted" | Automated attacks target everyone. Size does not matter. |
| "Security slows us down" | A breach slows you down 100x more. Build security in from the start. |
| "We will fix it after launch" | Vulnerabilities in production are exploited within hours. Fix before deploy. |