ZeroTrustKerberosLink Security Hardening Checklist¶

Overview¶

This security hardening checklist provides a comprehensive guide for securing ZeroTrustKerberosLink deployments. It covers default security settings, additional hardening steps, security configuration guidance, and monitoring recommendations. This checklist aligns with our security hardening priorities, including security code review, penetration testing remediation, secrets management, and compliance verification.

Default Security Settings¶

ZeroTrustKerberosLink comes with the following security features enabled by default:

Authentication and Authorization¶

Security Feature	Default Setting	Description
✅ Zero Trust Authentication	Enabled	Every access request is fully authenticated and authorized
✅ Multi-Factor Authentication	Optional	MFA can be required based on risk score
✅ Short-lived Credentials	1 hour	AWS credentials expire after 1 hour by default
✅ Least Privilege Access	Enabled	Users receive only the minimum required permissions
✅ Session Monitoring	Enabled	All authentication sessions are continuously monitored

Input Validation¶

Security Feature	Default Setting	Description
✅ HTTP Parameter Validation	Enabled	All HTTP parameters are validated
✅ JSON Payload Validation	Enabled	All JSON payloads are validated against schemas
✅ Path Traversal Protection	Enabled	Protection against path traversal attacks
✅ Content Type Validation	Enabled	Validation of Content-Type headers
✅ Character Encoding Validation	Enabled	Validation of character encodings

Security Headers¶

Security Feature	Default Setting	Description
✅ Content Security Policy	Strict	Default-src 'self' with limited exceptions
✅ HTTP Strict Transport Security	Enabled	max-age=31536000; includeSubDomains; preload
✅ X-Content-Type-Options	nosniff	Prevents MIME type sniffing
✅ X-Frame-Options	DENY	Prevents clickjacking attacks
✅ X-XSS-Protection	1; mode=block	Provides XSS protection
✅ Referrer-Policy	strict-origin-when-cross-origin	Controls referrer information
✅ Permissions-Policy	Restrictive	Restricts browser features

Encryption¶

Security Feature	Default Setting	Description
✅ TLS 1.2+	Enforced	Only TLS 1.2 or higher is allowed
✅ Strong Cipher Suites	Enforced	Only strong cipher suites are allowed
✅ Perfect Forward Secrecy	Enabled	Ensures forward secrecy for TLS connections
✅ Data-at-Rest Encryption	AES-256-GCM	All sensitive data is encrypted at rest
✅ Key Rotation	90 days	Encryption keys are rotated every 90 days

Network Security¶

Security Feature	Default Setting	Description
✅ Firewall Rules	Restrictive	Only required ports are open
✅ Network Segmentation	Enabled	Components are deployed in separate network segments
✅ DDoS Protection	Basic	Basic DDoS protection is enabled
✅ Rate Limiting	Enabled	Rate limiting for all API endpoints
✅ IP Allowlisting	Optional	IP allowlisting can be configured

Logging and Monitoring¶

Security Feature	Default Setting	Description
✅ Authentication Logging	Enabled	All authentication attempts are logged
✅ Authorization Logging	Enabled	All authorization decisions are logged
✅ API Access Logging	Enabled	All API access is logged
✅ Admin Action Logging	Enabled	All administrative actions are logged
✅ Log Integrity	Enabled	Logs are protected against tampering

Additional Hardening Steps¶

Beyond the default security settings, the following additional hardening steps are recommended:

Authentication and Authorization Hardening¶

Enforce Multi-Factor Authentication

# config.yaml
authentication:
  mfa:
    required: true
    methods:
      - totp
      - push
    grace_period: 0  # No grace period

Reduce Credential Lifetime

# config.yaml
aws:
  credentials:
    lifetime: 1800  # 30 minutes
    renewal_window: 300  # 5 minutes before expiration

Implement IP-Based Restrictions

# config.yaml
network:
  allowed_ips:
    - 192.168.1.0/24
    - 10.0.0.0/8
  denied_ips:
    - 1.2.3.4/32

Enable Just-In-Time Access

# config.yaml
authorization:
  just_in_time:
    enabled: true
    approval_required: true
    max_duration: 3600  # 1 hour

Implement Role-Based Access Control

# config.yaml
rbac:
  enabled: true
  roles:
    - name: admin
      permissions:
        - manage_users
        - manage_roles
        - view_audit_logs
    - name: user
      permissions:
        - authenticate
        - assume_role

Network Security Hardening¶

Implement Web Application Firewall

# config.yaml
waf:
  enabled: true
  rules:
    - name: block_sql_injection
      enabled: true
    - name: block_xss
      enabled: true
    - name: block_path_traversal
      enabled: true

Enable Advanced DDoS Protection

# config.yaml
ddos_protection:
  enabled: true
  protection_level: advanced
  auto_mitigation: true

Implement Network Intrusion Detection

# config.yaml
intrusion_detection:
  enabled: true
  alert_only: false
  rules:
    - source: emerging-threats
      enabled: true
    - source: custom
      path: /etc/zerotrustkerberoslink/ids-rules.conf

Configure TLS Certificate Pinning

# config.yaml
tls:
  certificate_pinning:
    enabled: true
    pins:
      - sha256/AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA=
      - sha256/BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB=

Implement DNS Security

# config.yaml
dns:
  dnssec: true
  dns_over_https: true
  dns_servers:
    - 8.8.8.8
    - 1.1.1.1

Logging and Monitoring Hardening¶

Enable Real-Time Security Monitoring

# config.yaml
monitoring:
  real_time:
    enabled: true
    alert_channels:
      - email
      - slack
      - pagerduty

Implement Log Forwarding to SIEM

# config.yaml
logging:
  siem_integration:
    enabled: true
    type: splunk
    url: https://splunk.example.com:8088
    token: ${SPLUNK_TOKEN}
    index: zerotrustkerberoslink

Enable User Behavior Analytics

# config.yaml
user_behavior_analytics:
  enabled: true
  baseline_period: 14  # days
  anomaly_detection:
    sensitivity: medium

Configure Automated Response Actions

# config.yaml
automated_response:
  enabled: true
  actions:
    - trigger: failed_authentication_attempts
      threshold: 5
      action: block_user
      duration: 3600  # 1 hour
    - trigger: suspicious_ip
      action: require_mfa

Implement Comprehensive Audit Logging

# config.yaml
audit_logging:
  enabled: true
  log_level: debug
  retention_period: 365  # days
  tamper_protection: true

Secrets Management Hardening¶

Use AWS Secrets Manager for Credentials

# config.yaml
secrets_management:
  provider: aws_secrets_manager
  secret_prefix: zerotrustkerberoslink/
  auto_rotation: true
  rotation_period: 30  # days

Implement Envelope Encryption

# config.yaml
encryption:
  envelope_encryption:
    enabled: true
    kms_key_id: arn:aws:kms:us-east-1:123456789012:key/abcd1234-a123-456a-a12b-a123b4cd56ef

Configure Secure Credential Storage

# config.yaml
credential_storage:
  memory_protection: true
  secure_wipe: true
  cache_ttl: 300  # 5 minutes

Implement Credential Rotation

# config.yaml
credential_rotation:
  enabled: true
  service_accounts:
    rotation_period: 30  # days
  database_credentials:
    rotation_period: 60  # days

Use Hardware Security Module

# config.yaml
hsm:
  enabled: true
  provider: aws_cloudhsm
  credentials:
    user: ${HSM_USER}
    password: ${HSM_PASSWORD}

Security Configuration Guide¶

Secure Deployment Architecture¶

ZeroTrustKerberosLink should be deployed using the following secure architecture:

                                  ┌─────────────────────┐
                                  │                     │
                                  │  AWS CloudWatch     │
                                  │                     │
                                  └─────────────────────┘
                                           ▲
                                           │
                                           │ Logs
                                           │
┌─────────────────┐              ┌─────────────────────┐
│                 │              │                     │
│  Enterprise     │              │  AWS KMS            │
│  Network        │              │                     │
│                 │              └─────────────────────┘
└────────┬────────┘                       ▲
         │                                │
         │                                │ Encryption
         │                                │
         │                      ┌─────────────────────┐
         │                      │                     │
         │                      │  AWS Secrets Manager│
         │                      │                     │
         │                      └─────────────────────┘
         │                                ▲
         │                                │
         │                                │ Secrets
         ▼                                │
┌─────────────────┐              ┌─────────────────────┐
│                 │              │                     │
│  Load Balancer  │──────────────▶  ZeroTrustKerberos │
│  with WAF       │              │  Link Servers      │
│                 │◀─────────────│                     │
└─────────────────┘              └─────────┬───────────┘
                                           │
                                           │
                                           ▼
                                 ┌─────────────────────┐
                                 │                     │
                                 │  AWS IAM/STS        │
                                 │                     │
                                 └─────────────────────┘

Security Configuration Checklist¶

1. Network Configuration¶

Deploy in a dedicated VPC
Use private subnets for application components
Implement security groups with minimal access
Configure network ACLs for additional protection
Enable VPC Flow Logs for network monitoring
Implement AWS Shield for DDoS protection
Configure AWS WAF with security rules

2. AWS IAM Configuration¶

Create dedicated IAM roles with least privilege
Implement permission boundaries for all roles
Enable AWS CloudTrail for API logging
Configure IAM Access Analyzer
Implement AWS Organizations SCPs
Enable MFA for all IAM users
Implement IAM credential rotation

3. Encryption Configuration¶

Create dedicated KMS keys for encryption
Enable automatic key rotation
Configure KMS key policies with least privilege
Implement envelope encryption for sensitive data
Enable S3 bucket encryption
Configure TLS 1.2+ for all communications
Implement certificate rotation

4. Logging and Monitoring Configuration¶

Configure CloudWatch Logs for all components
Set up CloudWatch Alarms for security events
Implement CloudWatch Dashboards for monitoring
Configure log retention policies
Set up log exports to S3 for long-term storage
Implement CloudWatch Events for automated responses
Configure AWS Config for configuration monitoring

5. Secrets Management Configuration¶

Configure AWS Secrets Manager for all secrets
Implement automatic secret rotation
Set up secure secret retrieval
Configure secret access policies
Implement secret encryption
Set up secret access logging
Configure secret backup and recovery

Security Monitoring Recommendations¶

Critical Security Metrics to Monitor¶

Metric	Description	Threshold	Response
Failed Authentication Attempts	Number of failed authentication attempts	5 in 5 minutes	Alert security team, temporarily block source IP
Unusual Role Assumptions	Unusual patterns in AWS role assumptions	Deviation from baseline	Alert security team, require additional verification
Credential Usage from New Locations	AWS credential usage from new geographic locations	Any occurrence	Alert security team, require MFA
Unusual API Calls	Unusual AWS API calls	Deviation from baseline	Alert security team, investigate activity
Configuration Changes	Changes to ZeroTrustKerberosLink configuration	Any occurrence	Alert security team, verify change authorization

CloudWatch Dashboard Configuration¶

Create a CloudWatch Dashboard with the following widgets:

Authentication Metrics
Failed authentication attempts
Successful authentication attempts
MFA usage
Authentication latency
Authorization Metrics
Role assumption counts by role
Permission denied events
Authorization latency
Temporary credential issuance
Security Events
Security policy violations
Configuration changes
Unusual activity alerts
WAF blocks
System Health
CPU utilization
Memory utilization
API latency
Error rates

CloudWatch Alarms¶

Configure the following CloudWatch Alarms:

Alarms:
  FailedAuthenticationAlarm:
    MetricName: FailedAuthenticationAttempts
    Namespace: ZeroTrustKerberosLink
    Statistic: Sum
    Period: 300
    EvaluationPeriods: 1
    Threshold: 5
    ComparisonOperator: GreaterThanThreshold
    AlarmActions:
      - arn:aws:sns:us-east-1:123456789012:SecurityAlerts

  UnusualRoleAssumptionAlarm:
    MetricName: UnusualRoleAssumptions
    Namespace: ZeroTrustKerberosLink
    Statistic: Sum
    Period: 300
    EvaluationPeriods: 1
    Threshold: 1
    ComparisonOperator: GreaterThanThreshold
    AlarmActions:
      - arn:aws:sns:us-east-1:123456789012:SecurityAlerts

  ConfigurationChangeAlarm:
    MetricName: ConfigurationChanges
    Namespace: ZeroTrustKerberosLink
    Statistic: Sum
    Period: 300
    EvaluationPeriods: 1
    Threshold: 0
    ComparisonOperator: GreaterThanThreshold
    AlarmActions:
      - arn:aws:sns:us-east-1:123456789012:SecurityAlerts

Log Insights Queries¶

Use the following CloudWatch Logs Insights queries for security monitoring:

Failed Authentication Analysis¶

filter eventType = "authentication" and success = false
| stats count(*) as failedCount by sourceIp, userIdentity
| sort failedCount desc

Unusual Role Assumption Analysis¶

filter eventType = "authorization" and action = "assumeRole"
| stats count(*) as assumeCount by userIdentity, roleArn, sourceIp
| sort assumeCount desc

Configuration Change Analysis¶

filter eventType = "configuration" and action = "update"
| parse message "changed by * from *" as actor, sourceIp
| stats count(*) as changeCount by actor, sourceIp, resource
| sort changeCount desc

Security Event Timeline¶

filter eventType in ["authentication", "authorization", "configuration", "security"]
| sort @timestamp asc
| display @timestamp, eventType, action, userIdentity, sourceIp, success, message

Conclusion¶

This security hardening checklist provides a comprehensive guide for securing ZeroTrustKerberosLink deployments. By implementing the default security settings, additional hardening steps, and following the security configuration and monitoring recommendations, organizations can ensure that their ZeroTrustKerberosLink deployment is secure and compliant with industry best practices.

The checklist aligns with our security hardening priorities: 1. Security Code Review: Ensuring secure configuration and implementation 2. Penetration Testing Remediation: Implementing controls to address common vulnerabilities 3. Secrets Management Review: Securing sensitive credentials and secrets 4. Compliance Verification: Ensuring compliance with industry standards and best practices

By following this checklist, organizations can maintain a strong security posture while leveraging the benefits of integrating Kerberos authentication with AWS services.