You must follow multiple best practices at all times when you operate your vCenter Server instances.

Table 1. Security Best Practices for Securing vCenter Server

Best Practice

Description

Assign correct roles to vCenter Server users.

VMW-VC-00415

Users and service accounts must be assigned only privileges they require. To reduce risk of confidentiality, availability, or integrity loss, the least privilege principle requires that these privileges must be assigned only if needed.

Use unique service accounts for applications that connect to vCenter Server.

VMW-VC-00401

Create a service account for each application that connects to vCenter Server. Grant only the required permissions for the application to run.

Restrict the use of the built-in single sign-on Administrator account.

VMW-VC-00439

Only use the [email protected] account for emergencies and situations where no other option exists. The built-in single sign-on account must not be used for daily operations. Set up a policy that restricts the use of the account.

vCenter Server must restrict access to cryptographic permissions.

VMW-VC-01211

These permissions must be reserved for cryptographic administrators where VM and/or vSAN encryption is in use. Catastrophic data loss can result from a poorly administered cryptography. Only the Administrator and any site-specific cryptographic group must have the following permissions:

  • Cryptographic Operations privileges

  • Global.Diagnostics

  • Host.Inventory.Add host to cluster

  • Host.Inventory.Add standalone host

  • Host.Local operations.Manage user groups

Use templates to deploy virtual machines.

VMW-VC-01235

To create application-specific templates, use templates that contain a hardened, patched, and properly configured operating system . You can also use the application template to deploy virtual machines.

The vCenter Server must use LDAPS when adding an SSO identity source.

VMW-VC-01229

To protect the integrity of LDAP communications, secure LDAP (LDAPS) must be explicitly configured when adding an LDAP identity source in vSphere SSO. When configuring an identity source and supplying an SSL certificate, vCenter Server enforces secure LDAP.

The vCenter Server must implement Active Directory authentication

VMW-VC-01228

The vCenter Server must ensure users are authenticated with an individual authenticator prior to using a group authenticator. Using Active Directory for authentication provides more robust account management capabilities.

The vCenter Server must use a limited privilege account when adding an LDAP identity source

VMW-VC-01230

When adding an LDAP identity source to vSphere SSO, the account used to bind to the AD must be minimally privileged. This account only requires read rights to the base DN specified. Any other permissions inside or outside of that OU are unnecessary and violate least privilege.

Backup the vCenter Native Key Providers with a strong password.

VMW-VC-01239

The vCenter Native Key Provider acts as a key provider for encryption based capabilities, such as encrypted virtual machines, without requiring an external KMS solution. When activating this feature, a backup PCKS#12 file is created. If no password is provided during the backup process, the backup file can be used maliciously and compromise the environment.

Restrict access to the cryptographic role.

VMW-VC-01210

The built-in Administrator role has the permission to perform cryptographic operations, such as Key Management Server (KMS) functions and encrypting and decrypting virtual machine disks. This role must be reserved for cryptographic administrators, where virtual machine or vSAN encryption is required. All other vSphere administrators, who do not require cryptographic operations, must be assigned the No cryptography administrator role.

The vCenter Server Machine SSL certificate must be issued by an appropriate certificate authority.

VMW-VC-01205

The default self-signed, VMCA-issued vCenter reverse proxy certificate must be replaced with an approved certificate. The use of an approved certificate on the vCenter reverse proxy and other services assures clients that the service they are connecting to is legitimate and trusted.

Ensure that participation in CDP or LLDP is intentional.

VMW-VC-01247

The vSphere VDS can participate in Cisco Discovery Protocol (CDP) or Link Layer Discovery Protocol (LLDP), as a listener, advertiser, or both. This can facilitate improved mapping network topology and troubleshooting, however you must ensure that information sent and received is intentional, as this information can be used by an adversary to gain a better understanding of your environment.

Ensure that port mirroring is used legitimately.

VMW-VC-01248

The vSphere VDS can mirror traffic from one port to another, allowing observation of traffic. Ensure that port mirroring is used legitimately.

Configure the vCenter Server firewall for additional defense-in-depth.

VMW-VC-01251

vCenter Server has its own firewall settings that can be used in conjunction with a network/perimeter firewall for additional defense. Ensure that you configure it with accept rules for your workstations prior to configuring deny rules.

Remove unnecessary NICs.

VMW-VC-01252

In Center Server, you can configure multiple network interfaces connected to different networks. If a system has interfaces on different networks, there is potential to bridge the networks, or create a backdoor that circumvents network-based access controls. Ensure that all NICs are configured properly and are necessary.

Install security patches and updates for vCenter Server.

VMW-VC-01253

You install all security patches and updates on vCenter Server instances as soon as possible. An attacker can exploit known vulnerabilities when attempting to attain access or elevate privileges. Mitigate the risk of breaches by updating vCenter Server instances first and then updating ESXi hosts.

Configure Key Encryption Keys (KEKs) to be re-issued at regular intervals for the vSAN encrypted datastores.

VMW-VC-01213

Interview the SA to determine whether a procedure exists to perform a shallow re-key of all vSAN encrypted datastores at regular, site-defined intervals. This interval must be defined by the SA and the ISSO. If vSAN encryption is not in use, this is not applicable.