The Windows DNS Server must protect secret/private cryptographic keys while at rest.

Severity	Group ID	Group Title	Version	Rule ID	Date	STIG Version
medium	V-259393	SRG-APP-000231-DNS-000033	WDNS-22-000065	SV-259393r1028387_rule	2025-02-25	2

Description
Information at rest refers to the state of information when it is located on a secondary storage device within an organizational information system. Mobile devices, laptops, desktops, and storage devices can be either lost or stolen, and the contents of their data storage (e.g., hard drives and nonvolatile memory) can be read, copied, or altered. Applications and application users generate information throughout the course of their application use. The DNS server must protect the confidentiality and integrity of shared keys for TSIG and private keys for SIG(0) and must protect the integrity of DNS information. There is no need to protect the confidentiality of DNS information because it is accessible by all devices that can contact the server.

Description

Information at rest refers to the state of information when it is located on a secondary storage device within an organizational information system. Mobile devices, laptops, desktops, and storage devices can be either lost or stolen, and the contents of their data storage (e.g., hard drives and nonvolatile memory) can be read, copied, or altered. Applications and application users generate information throughout the course of their application use. The DNS server must protect the confidentiality and integrity of shared keys for TSIG and private keys for SIG(0) and must protect the integrity of DNS information. There is no need to protect the confidentiality of DNS information because it is accessible by all devices that can contact the server.

ℹ️ Check
This check is not applicable for Windows DNS Servers that only host Active Directory-integrated zones or for Windows DNS servers on a classified network. To verify the cryptographic keys are protected after being backed up to another medium (tape, disk, SAN, etc.), consult with the system administrator to determine the backup policy in place for the DNS server. If a backup policy does not exist or the backup policy does not specify the protection required for the backup medium to be at or above the level as the server, this is a finding.

ℹ️ Check

This check is not applicable for Windows DNS Servers that only host Active Directory-integrated zones or for Windows DNS servers on a classified network. To verify the cryptographic keys are protected after being backed up to another medium (tape, disk, SAN, etc.), consult with the system administrator to determine the backup policy in place for the DNS server. If a backup policy does not exist or the backup policy does not specify the protection required for the backup medium to be at or above the level as the server, this is a finding.

✔️ Fix
To ensure the cryptographic keys are protected after being backed up to tape or other medium, develop a backup policy that includes the protection of backup date at or above the level as the DNS server.