Google CloudOverview
NOTE: Currently, the SHA1 algorithm has been removed from general use by Google, and, if being used, needs to be whitelisted on a project basis by Google and will also, therefore, require a Google Cloud support contract.
DNSSEC algorithm numbers in this registry may be used in CERT RRs. Zone signing (DNSSEC) and transaction security mechanisms (SIG(0) and TSIG) make use of particular subsets of these algorithms. The algorithm used for key signing should be a recommended one and it should be strong.
Rationale
Domain Name System Security Extensions (DNSSEC) algorithm numbers in this registry may be used in CERT RRs. Zone signing (DNSSEC) and transaction security mechanisms (SIG(0) and TSIG) make use of particular subsets of these algorithms.
The algorithm used for key signing should be a recommended one and it should be strong. When enabling DNSSEC for a managed zone, or creating a managed zone with DNSSEC, the user can select the DNSSEC signing algorithms and the denial-ofexistence type. Changing the DNSSEC settings is only effective for a managed zone if DNSSEC is not already enabled. If there is a need to change the settings for a managed zone where it has been enabled, turn DNSSEC off and then re-enable it with different settings.
Remediation guidance
Using Google Cloud CLI
- If it is necessary to change the settings for a managed zone where it has been enabled, NSSEC must be turned off and re-enabled with different settings. To turn off DNSSEC, run the following command:
gcloud dns managed-zones update <zoneName> --dnssec-state off
- To update zone-signing for a reported managed DNS Zone, run the following command:
gcloud dns managed-zones update <zoneName> --dnssec-state on --ksk-algorithm --ksk-key-length --zsk-algorithm --zsk-key-length --denial-of-existence <denialOfExistence>
Default value
- RSASHA1 key-signing support may be required for compatibility reasons.
- Remediation CLI works well with gcloud-cli version 221.0.0 and later.
References
- https://cloudplatform.googleblog.com/2017/11/DNSSEC-now-available-in-Cloud-DNS.html
- https://cloud.google.com/dns/dnssec-config#enabling
- https://cloud.google.com/dns/dnssec
Additional Information
- RSASHA1 key-signing support may be required for compatibility reasons.
- Remediation CLI works well with gcloud-cli version 221.0.0 and later.
Google Cloud Console (Asset-Level)
- Open the affected project/resource from the finding details in Google Cloud Console.
- Navigate to the resource security/configuration settings.
- Apply the control-specific secure configuration.
- Save and re-run the check.
Multiple Remediation Paths
Google Cloud
SERVICE-WIDE (RECOMMENDED when many resources are affected): Enforce Organization Policies at org/folder level so new resources inherit secure defaults.
gcloud org-policies set-policy policy.yaml
ASSET-LEVEL: Use the product-specific remediation steps above for only the impacted project/resources.
PREVENTIVE: Use org policy constraints/custom constraints and enforce checks in deployment pipelines.
References for Service-Wide Patterns
- GCP Organization Policy overview: https://cloud.google.com/resource-manager/docs/organization-policy/overview
- GCP Organization policy constraints catalog: https://cloud.google.com/resource-manager/docs/organization-policy/org-policy-constraints
- gcloud org-policies: https://cloud.google.com/sdk/gcloud/reference/org-policies
Operational Rollout Workflow
Use this sequence to reduce risk and avoid repeated drift.
1. Contain at Service-Wide Scope First (Recommended)
- Google Cloud: apply organization policy constraints at org/folder scope.
gcloud org-policies set-policy policy.yaml
2. Remediate Existing Affected Assets
- Execute the control-specific Console/CLI steps documented above for each flagged resource.
- Prioritize internet-exposed and production assets first.
3. Validate and Prevent Recurrence
- Re-scan after each remediation batch.
- Track exceptions with owner and expiry date.
- Add preventive checks in IaC/CI pipelines.
Query logic
These are the stored checks tied to this control.
RSASHA1 is not used for the zone-signing key in Cloud DNS DNSSEC
Connectors
Covered asset types
Expected check: eq []
managedZones(where:{hasDNSKeySpec_SOME:{keyType:"zoneSigning",algorithm_MATCHES:"(?i)rsasha1"}}){...AssetFragment}
