The vCenter Server must have new Key Encryption Keys (KEKs) reissued at regular intervals for vSAN encrypted datastore(s).

Severity	Group ID	Group Title	Version	Rule ID	Date	STIG Version
medium	V-258954	SRG-APP-000516	VCSA-80-000287	SV-258954r1003610_rule	2024-12-16	2

Description
The KEK for a vSAN encrypted datastore is generated by the Key Management Server (KMS) and serves as a wrapper and lock around the Disk Encryption Key (DEK). The DEK is generated by the host and is used to encrypt and decrypt the datastore. A shallow rekey is a procedure in which the KMS issues a new KEK to the ESXi host, which rewraps the DEK but does not change the DEK or any data on disk. This operation must be done on a regular, site-defined interval and can be viewed as similar in criticality to changing an administrative password. If the KMS is compromised, a standing operational procedure to rekey will put a time limit on the usefulness of any stolen KMS data.

Description

The KEK for a vSAN encrypted datastore is generated by the Key Management Server (KMS) and serves as a wrapper and lock around the Disk Encryption Key (DEK). The DEK is generated by the host and is used to encrypt and decrypt the datastore. A shallow rekey is a procedure in which the KMS issues a new KEK to the ESXi host, which rewraps the DEK but does not change the DEK or any data on disk. This operation must be done on a regular, site-defined interval and can be viewed as similar in criticality to changing an administrative password. If the KMS is compromised, a standing operational procedure to rekey will put a time limit on the usefulness of any stolen KMS data.

ℹ️ Check
If vSAN is not in use, this is not applicable. Interview the system administrator (SA) to determine that a procedure has been put in place to perform a shallow rekey of all vSAN encrypted datastores at regular, site-defined intervals. VMware recommends a 60-day rekey task, but this interval must be defined by the SA and the ISSO. If vSAN encryption is not in use, this is not a finding. If vSAN encryption is in use and a regular rekey procedure is not in place, this is a finding.

ℹ️ Check

If vSAN is not in use, this is not applicable. Interview the system administrator (SA) to determine that a procedure has been put in place to perform a shallow rekey of all vSAN encrypted datastores at regular, site-defined intervals. VMware recommends a 60-day rekey task, but this interval must be defined by the SA and the ISSO. If vSAN encryption is not in use, this is not a finding. If vSAN encryption is in use and a regular rekey procedure is not in place, this is a finding.

✔️ Fix
If vSAN encryption is in use, ensure a regular rekey procedure is in place. To generate new encryption keys for vSAN, do the following: From the vSphere Client, go to Host and Clusters. Select the vCenter Server >> Select the cluster >> Configure >> vSAN >> Services >> Data Services. Select "Generate New Encryption Keys" and optionally generate new DEKs and click "Generate".