Azure DNS Security Checklist

1. Identity and Access Management

1. Use Microsoft Entra ID for all DNS management operations
2. Enforce Role-Based Access Control with least privilege
3. Assign DNS Zone Contributor roles only where required
4. Avoid broad roles such as Owner or Contributor at the subscription level 
5. Use Privileged Identity Management for DNS administrators
6. Enable Multi-Factor Authentication for all privileged users
7. Review role assignments regularly and remove unused access

2. DNS Zone Protection

1. Restrict access to DNS zones using RBAC
2. Use resource locks to prevent accidental deletion
3. Separate production and non-production DNS zones
4. Avoid exposing internal records in public DNS zones
5. Use naming conventions to clearly identify zone purpose
6. Monitor changes to DNS records

3. Private DNS and Internal Resolution

1. Use Private DNS zones for internal name resolution
2. Link Private DNS zones only to required virtual networks
3. Avoid overly broad VNet linking
4. Use split-brain DNS design where required
5. Secure hybrid name resolution with proper forwarding rules
6. Limit access to private DNS zones

4. Network Security and Name Resolution

1. Use Azure DNS with Private Endpoints where applicable
2. Secure DNS resolution paths between on-premises and Azure
3. Restrict DNS traffic using NSGs and firewalls
4. Monitor DNS query traffic
5. Use Azure Firewall DNS proxy if required
6. Prevent unauthorized DNS forwarding

5. DNS Record Management

1. Regularly audit DNS records
2. Remove stale or unused records
3. Avoid wildcard DNS entries unless required
4. Validate all external-facing records
5. Use low TTL for dynamic environments where appropriate
6. Document critical DNS records

6. Logging and Monitoring

1. Enable diagnostic logs for DNS zones
2. Send logs to Log Analytics or SIEM
3. Monitor DNS queries and changes
4. Set alerts for unauthorized modifications
5. Track record creation and deletion events
6. Review logs regularly

7. Threat Protection and Risk Mitigation

1. Monitor for DNS hijacking attempts
2. Detect unauthorized zone transfers
3. Watch for suspicious record changes
4. Protect against domain takeover scenarios
5. Validate ownership of all domains
6. Regularly audit domain registrations

8. Integration and Hybrid Security

1. Secure DNS integration with on-premises environments
2. Use conditional forwarding securely
3. Protect DNS servers used in hybrid configurations
4. Ensure secure communication between DNS resolvers
5. Avoid open recursive DNS configurations

9. Governance and Compliance

1. Use Azure Policy to enforce DNS configurations
2. Standardize DNS naming and structure
3. Document DNS architecture
4. Implement change control processes
5. Regularly review compliance requirements
6. Enforce tagging and classification

10. Backup and Recovery

1. Export DNS zone configurations regularly
2. Maintain backup of DNS records
3. Test restore procedures
4. Document recovery steps
5. Protect critical zones from accidental deletion

11. Continuous Security Operations

1. Perform regular DNS security assessments
2. Audit DNS configurations periodically
3. Continuously monitor DNS activity
4. Update configurations based on evolving threats
5. Validate security posture regularly
6. Maintain documentation

 Always use best practices. Never assume trust. Always verify access. Security is not static and must be continuously monitored, reviewed, and improved.