| V-93977 | High | The ESXi host SSH daemon must not allow authentication using an empty password. | Configuring this setting for the SSH daemon provides additional assurance that remote login via SSH will require a password, even in the event of misconfiguration elsewhere. |
| V-93969 | High | The ESXi host SSH daemon must be configured to use only the SSHv2 protocol. | SSH protocol version 1 suffers from design flaws that result in security vulnerabilities and should not be used. Only SSH protocol version 2 connections should be permitted. |
| V-94041 | High | The ESXi Image Profile and VIB Acceptance Levels must be verified. | Verify the ESXi Image Profile to only allow signed VIBs. An unsigned VIB represents untested code installed on an ESXi host. The ESXi Image profile supports four acceptance levels:
(1)... |
| V-94479 | High | The ESXi host must have all security patches and updates installed. | Installing software updates is a fundamental mitigation against the exploitation of publicly-known vulnerabilities. |
| V-94477 | High | The ESXi host must verify the integrity of the installation media before installing ESXi. | Always check the SHA1 or MD5 hash after downloading an ISO, offline bundle, or patch to ensure integrity and authenticity of the downloaded files. |
| V-94067 | High | The virtual switch MAC Address Change policy must be set to reject on the ESXi host. | If the virtual machine operating system changes the MAC address, it can send frames with an impersonated source MAC address at any time. This allows it to stage malicious attacks on the devices in... |
| V-94019 | Medium | The ESXi host must disable ESXi Shell unless needed for diagnostics or troubleshooting. | The ESXi Shell is an interactive command line environment available locally from the DCUI or remotely via SSH. Activities performed from the ESXi Shell bypass vCenter RBAC and audit controls. The... |
| V-94017 | Medium | The ESXi host must be configured to disable non-essential capabilities by disabling SSH. | The ESXi Shell is an interactive command line interface (CLI) available at the ESXi server console. The ESXi shell provides temporary access to commands essential for server maintenance. Intended... |
| V-94013 | Medium | The password hashes stored on the ESXi host must have been generated using a FIPS 140-2 approved cryptographic hashing algorithm. | Systems must employ cryptographic hashes for passwords using the SHA-2 family of algorithms or FIPS 140-2 approved successors. The use of unapproved algorithms may result in weak password hashes... |
| V-94015 | Medium | The ESXi host must disable the Managed Object Browser (MOB). | The Managed Object Browser (MOB) provides a way to explore the object model used by the VMkernel to manage the host and enables configurations to be changed as well. This interface is meant to be... |
| V-94029 | Medium | The ESXi host must set a timeout to automatically disable idle sessions after 10 minutes. | If a user forgets to log out of their SSH session, the idle connection will remains open indefinitely, increasing the potential for someone to gain privileged access to the host. The... |
| V-94545 | Medium | The ESXi host must implement replay-resistant authentication mechanisms for network access to non-privileged accounts by using the vSphere Authentication Proxy. | If you configure your host to join an Active Directory domain using Host Profiles the Active Directory credentials are saved in the host profile and are transmitted over the network. To avoid... |
| V-93949 | Medium | The ESXi host must limit the number of concurrent sessions to ten for all accounts and/or account types by enabling lockdown mode. | Enabling lockdown mode disables direct access to an ESXi host requiring the host be managed remotely from vCenter Server. This is done to ensure the roles and access controls implemented in... |
| V-94531 | Medium | The ESXi host must implement replay-resistant authentication mechanisms for network access to privileged accounts by using the vSphere Authentication Proxy. | If you configure your host to join an Active Directory domain using Host Profiles the Active Directory credentials are saved in the host profile and are transmitted over the network. To avoid... |
| V-94011 | Medium | The ESXi host must prohibit the reuse of passwords within five iterations. | If a user, or root, used the same password continuously or was allowed to change it back shortly after being forced to change it to something else, it would provide a potential intruder with the... |
| V-93959 | Medium | The ESXi host must enforce the unlock timeout of 15 minutes after a user account is locked out. | By limiting the number of failed login attempts, the risk of unauthorized access via user password guessing, otherwise known as brute-forcing, is reduced. Limits are imposed by locking the account. |
| V-93955 | Medium | Remote logging for ESXi hosts must be configured. | Remote logging to a central log host provides a secure, centralized store for ESXi logs. By gathering host log files onto a central host it can more easily monitor all hosts with a single tool. It... |
| V-93957 | Medium | The ESXi host must enforce the limit of three consecutive invalid logon attempts by a user. | By limiting the number of failed login attempts, the risk of unauthorized access via user password guessing, otherwise known as brute-forcing, is reduced. Limits are imposed by locking the account. |
| V-94507 | Medium | The ESXi host must require individuals to be authenticated with an individual authenticator prior to using a group authenticator by using the vSphere Authentication Proxy. | If you configure your host to join an Active Directory domain using Host Profiles the Active Directory credentials are saved in the host profile and are transmitted over the network. To avoid... |
| V-93961 | Medium | The ESXi host must display the Standard Mandatory DoD Notice and Consent Banner before granting access to the system. | Failure to display the DoD logon banner prior to a log in attempt will negate legal proceedings resulting from unauthorized access to system resources. |
| V-93963 | Medium | The ESXi host must display the Standard Mandatory DoD Notice and Consent Banner before granting access to the system. | Failure to display the DoD logon banner prior to a log in attempt will negate legal proceedings resulting from unauthorized access to system resources. |
| V-93971 | Medium | The ESXi host SSH daemon must ignore .rhosts files. | SSH trust relationships mean a compromise on one host can allow an attacker to move trivially to other hosts. SSH can emulate the behavior of the obsolete rsh command in allowing users to enable... |
| V-93965 | Medium | The ESXi host SSH daemon must be configured with the Department of Defense (DoD) login banner. | The warning message reinforces policy awareness during the logon process and facilitates possible legal action against attackers. Alternatively, systems whose ownership should not be obvious... |
| V-93967 | Medium | The ESXi host SSH daemon must use DoD-approved encryption to protect the confidentiality of remote access sessions. | Approved algorithms should impart some level of confidence in their implementation. Limit the ciphers to those algorithms which are FIPS-approved. Counter (CTR) mode is also preferred over... |
| V-94037 | Medium | The ESXi host must enable a persistent log location for all locally stored logs. | ESXi can be configured to store log files on an in-memory file system. This occurs when the host's "/scratch" directory is linked to "/tmp/scratch". When this is done only a single day's worth of... |
| V-94033 | Medium | The ESXi host must logout of the console UI after 10 minutes. | When the Direct console user interface (DCUI) is enabled and logged in it should be automatically logged out if left logged in to avoid unauthorized privilege gains. The DcuiTimeOut defines a... |
| V-94031 | Medium | The ESXi host must terminate shell services after 10 minutes. | When the ESXi Shell or SSH services are enabled on a host they will run indefinitely. To avoid having these services left running set the ESXiShellTimeOut. The ESXiShellTimeOut defines a window... |
| V-94039 | Medium | The ESXi host must configure NTP time synchronization. | To assure the accuracy of the system clock, it must be synchronized with an authoritative time source within DoD. Many system functions, including time-based login and activity restrictions,... |
| V-94349 | Medium | The ESXi host must not provide root/administrator level access to CIM-based hardware monitoring tools or other third-party applications. | The CIM system provides an interface that enables hardware-level management from remote applications via a set of standard APIs. Create a limited-privilege, read-only service account for CIM.... |
| V-94043 | Medium | The ESXi host must protect the confidentiality and integrity of transmitted information by isolating vMotion traffic. | While encrypted vMotion is available now vMotion traffic should still be sequestered from other traffic to further protect it from attack. This network must be only be accessible to other ESXi... |
| V-94047 | Medium | The ESXi host must protect the confidentiality and integrity of transmitted information by protecting IP based management traffic. | Virtual machines might share virtual switches and VLANs with the IP-based storage configurations. IP-based storage includes vSAN, iSCSI and NFS. This configuration might expose IP-based storage... |
| V-93989 | Medium | The ESXi host SSH daemon must not allow compression or must only allow compression after successful authentication. | If compression is allowed in an SSH connection prior to authentication, vulnerabilities in the compression software could result in compromise of the system from an unauthenticated connection,... |
| V-93981 | Medium | The ESXi host SSH daemon must be configured to only use Message Authentication Codes (MACs) employing FIPS 140-2 approved cryptographic hash algorithms. | DoD information systems are required to use FIPS 140-2 approved cryptographic hash functions. |
| V-93987 | Medium | The ESXi host SSH daemon must perform strict mode checking of home directory configuration files. | If other users have access to modify user-specific SSH configuration files, they may be able to log into the system as another user. |
| V-94053 | Medium | SNMP must be configured properly on the ESXi host. | If SNMP is not being used, it must remain disabled. If it is being used, the proper trap destination must be configured. If SNMP is not properly configured, monitoring information can be sent to a... |
| V-93973 | Medium | The ESXi host SSH daemon must not allow host-based authentication. | SSH trust relationships mean a compromise on one host can allow an attacker to move trivially to other hosts. SSH's cryptographic host-based authentication is more secure than ".rhosts"... |
| V-94059 | Medium | The ESXi host must configure the firewall to restrict access to services running on the host. | Unrestricted access to services running on an ESXi host can expose a host to outside attacks and unauthorized access. Reduce the risk by configuring the ESXi firewall to only allow access from... |
| V-93979 | Medium | The ESXi host SSH daemon must not permit user environment settings. | SSH environment options potentially allow users to bypass access restriction in some configurations. Users must not be able to present environment options to the SSH daemon. |
| V-93993 | Medium | The ESXi host SSH daemon must be configured to not allow X11 forwarding. | X11 forwarding over SSH allows for the secure remote execution of X11-based applications. This feature can increase the attack surface of an SSH connection. |
| V-93995 | Medium | The ESXi host SSH daemon must not accept environment variables from the client. | Environment variables can be used to change the behavior of remote sessions and should be limited. Locale environment variables that specify the language, character set, and other features... |
| V-93997 | Medium | The ESXi host SSH daemon must not permit tunnels. | OpenSSH has the ability to create network tunnels (layer-2 and layer-3) over an SSH connection. This function can provide similar convenience to a Virtual Private Network (VPN) with the similar... |
| V-94069 | Medium | The virtual switch Promiscuous Mode policy must be set to reject on the ESXi host. | When promiscuous mode is enabled for a virtual switch all virtual machines connected to the Portgroup have the potential of reading all packets across that network, meaning only the virtual... |
| V-94065 | Medium | The virtual switch Forged Transmits policy must be set to reject on the ESXi host. | If the virtual machine operating system changes the MAC address, the operating system can send frames with an impersonated source MAC address at any time. This allows an operating system to stage... |
| V-94061 | Medium | The ESXi host must configure the firewall to block network traffic by default. | In addition to service specific firewall rules ESXi has a default firewall rule policy to allow or deny incoming and outgoing traffic. Reduce the risk of attack by making sure this is set to deny... |
| V-94023 | Medium | The ESXi host must use the vSphere Authentication Proxy to protect passwords when adding ESXi hosts to Active Directory. | If you configure your host to join an Active Directory domain using Host Profiles the Active Directory credentials are saved in the host profile and are transmitted over the network. To avoid... |
| V-94009 | Medium | The ESXi host must enforce password complexity by requiring that at least one upper-case character be used. | To enforce the use of complex passwords, minimum numbers of characters of different classes are mandated. The use of complex passwords reduces the ability of attackers to successfully obtain valid... |
| V-94005 | Medium | The ESXi host must remove keys from the SSH authorized_keys file. | ESXi hosts come with SSH which can be enabled to allow remote access without requiring user authentication. To enable password free access copy the remote users public key into the... |
| V-94003 | Medium | The ESXi host SSH daemon must limit connections to a single session. | The SSH protocol has the ability to provide multiple sessions over a single connection without reauthentication. A compromised client could use this feature to establish additional sessions to a... |
| V-94083 | Medium | All ESXi host-connected virtual switch VLANs must be fully documented and have only the required VLANs. | When defining a physical switch port for trunk mode, only specified VLANs must be configured on the VLAN trunk link. The risk with not fully documenting all VLANs on the vSwitch is that it is... |
| V-94483 | Medium | The ESXi host must exclusively enable TLS 1.2 for the ioFilter, vSANVP and reverse proxy services. | TLS 1.0 and 1.1 are deprecated protocols with well published shortcomings and vulnerabilities. TLS 1.2 should be enabled on all interfaces and SSLv3, TL 1.1 and 1.0 disabled where supported.... |
| V-94481 | Medium | The ESXi host must enable TLS 1.2 exclusively for the SFCB service. | TLS 1.0 and 1.1 are deprecated protocols with well published shortcomings and vulnerabilities. TLS 1.2 should be enabled on all interfaces and SSLv3, TL 1.1 and 1.0 disabled where supported.... |
| V-94487 | Medium | The ESXi host must enable Secure Boot. | Secure Boot is a protocol of UEFI firmware that ensures the integrity of the boot process from hardware up through to the OS. Secure Boot for ESXi requires support from the firmware and it... |
| V-94489 | Medium | The ESXi host must use DoD-approved certificates. | The default self-signed, VMCA issued host certificate must be replaced with a DoD-approved certificate. The use of a DoD certificate on the host assures clients that the service they are... |
| V-94079 | Medium | For physical switch ports connected to the ESXi host, the non-negotiate option must be configured for trunk links between external physical switches and virtual switches in VST mode. | In order to communicate with virtual switches in VST mode, external switch ports must be configured as trunk ports. VST mode does not support Dynamic Trunking Protocol (DTP), so the trunk must be... |
| V-94073 | Medium | For the ESXi host all port groups must be configured to a value other than that of the native VLAN. | ESXi does not use the concept of native VLAN. Frames with VLAN specified in the port group will have a tag, but frames with VLAN not specified in the port group are not tagged and therefore will... |
| V-94071 | Medium | The ESXi host must prevent unintended use of the dvFilter network APIs. | If you are not using products that make use of the dvfilter network API, the host should not be configured to send network information to a VM. If the API is enabled an attacker might attempt to... |
| V-94077 | Medium | For the ESXi host all port groups must not be configured to VLAN values reserved by upstream physical switches. | Certain physical switches reserve certain VLAN IDs for internal purposes and often disallow traffic configured to these values. For example, Cisco Catalyst switches typically reserve VLANs... |
| V-94075 | Medium | For the ESXi host all port groups must not be configured to VLAN 4095 unless Virtual Guest Tagging (VGT) is required. | When a port group is set to VLAN 4095, this activates VGT mode. In this mode, the vSwitch passes all network frames to the guest VM without modifying the VLAN tags, leaving it up to the guest to... |
| V-94549 | Low | The ESXi host must only allow the use of DoD PKI-established certificate authorities for verification of the establishment of protected sessions. | To assure accountability and prevent unauthenticated access, privileged users must utilize multifactor authentication to prevent potential misuse and compromise of the system. |
| V-94547 | Low | The ESXi host must implement replay-resistant authentication mechanisms for network access to non-privileged accounts by restricting use of Active Directory ESX Admin group membership. | When adding ESXi hosts to Active Directory, if the group "ESX Admins" exists, all user/group accounts assigned to the group will have full administrative access to the host. Discretion should be... |
| V-94543 | Low | The ESXi host must implement replay-resistant authentication mechanisms for network access to non-privileged accounts by using Active Directory for local user authentication. | Join ESXi hosts to an Active Directory (AD) domain to eliminate the need to create and maintain multiple local user accounts. Using AD for user authentication simplifies the ESXi host... |
| V-94533 | Low | The ESXi host must implement replay-resistant authentication mechanisms for network access to privileged accounts by restricting use of Active Directory ESX Admin group membership. | When adding ESXi hosts to Active Directory, if the group "ESX Admins" exists, all user/group accounts assigned to the group will have full administrative access to the host. Discretion should be... |
| V-94025 | Low | Active Directory ESX Admin group membership must not be used when adding ESXi hosts to Active Directory. | When adding ESXi hosts to Active Directory, if the group "ESX Admins" exists, all user/group accounts assigned to the group will have full administrative access to the host. Discretion should be... |
| V-94535 | Low | The ESXi host must electronically verify Personal Identity Verification (PIV) credentials. | To assure accountability and prevent unauthenticated access, privileged users must utilize multifactor authentication to prevent potential misuse and compromise of the system. |
| V-94529 | Low | The ESXi host must implement replay-resistant authentication mechanisms for network access to privileged accounts by using Active Directory for local user authentication. | Join ESXi hosts to an Active Directory (AD) domain to eliminate the need to create and maintain multiple local user accounts. Using AD for user authentication simplifies the ESXi host... |
| V-93951 | Low | The ESXi host must verify the DCUI.Access list. | Lockdown mode disables direct host access requiring that admins manage hosts from vCenter Server. However, if a host becomes isolated from vCenter Server, the admin is locked out and can no... |
| V-93953 | Low | The ESXi host must verify the exception users list for lockdown mode. | In vSphere you can add users to the Exception Users list from the vSphere Web Client. These users do not lose their permissions when the host enters lockdown mode. Usually you may want to add... |
| V-93975 | Low | The ESXi host SSH daemon must not permit root logins. | Permitting direct root login reduces auditable information about who ran privileged commands on the system and also allows direct attack attempts on root's password. |
| V-94055 | Low | The ESXi host must enable bidirectional CHAP authentication for iSCSI traffic. | When enabled, vSphere performs bidirectional authentication of both the iSCSI target and host. There is a potential for a MiTM attack, when not authenticating both the iSCSI target and host, in... |
| V-94035 | Low | The ESXi host must enable kernel core dumps. | In the event of a system failure, the system must preserve any information necessary to determine cause of failure and any information necessary to return to operations with least disruption to... |
| V-94505 | Low | The ESXi host must require individuals to be authenticated with an individual authenticator prior to using a group authenticator by using Active Directory for local user authentication. | Join ESXi hosts to an Active Directory (AD) domain to eliminate the need to create and maintain multiple local user accounts. Using AD for user authentication simplifies the ESXi host... |
| V-94511 | Low | The ESXi host must accept Personal Identity Verification (PIV) credentials. | To assure accountability and prevent unauthenticated access, privileged users must utilize multifactor authentication to prevent potential misuse and compromise of the system. |
| V-94049 | Low | The ESXi host must protect the confidentiality and integrity of transmitted information. | From the vSphere Web Client select the ESXi Host and go to Configure >> Networking >> VMkernel adapters. Review each VMkernel adapter that is defined and ensure it is enabled for only one type of... |
| V-93983 | Low | The ESXi host SSH daemon must not permit GSSAPI authentication. | GSSAPI authentication is used to provide additional authentication mechanisms to applications. Allowing GSSAPI authentication through SSH exposes the system’s GSSAPI to remote hosts, increasing... |
| V-93985 | Low | The ESXi host SSH daemon must not permit Kerberos authentication. | Kerberos authentication for SSH is often implemented using GSSAPI. If Kerberos is enabled through SSH, the SSH daemon provides a means of access to the system's Kerberos implementation. ... |
| V-94051 | Low | The ESXi host must protect the confidentiality and integrity of transmitted information by utilizing different TCP/IP stacks where possible. | There are three different TCP/IP stacks by default available on ESXi now which are Default, Provisioning, and vMotion. To better protect and isolate sensitive network traffic within ESXi admins... |
| V-94057 | Low | The ESXi host must disable Inter-VM transparent page sharing. | Published academic papers have demonstrated that by forcing a flush and reload of cache memory, it is possible to measure memory timings to try and determine an AES encryption key in use on... |
| V-94509 | Low | The ESXi host must require individuals to be authenticated with an individual authenticator prior to using a group authenticator by restricting use of Active Directory ESX Admin group membership. | When adding ESXi hosts to Active Directory, if the group "ESX Admins" exists, all user/group accounts assigned to the group will have full administrative access to the host. Discretion should be... |
| V-93999 | Low | The ESXi host SSH daemon must set a timeout count on idle sessions. | This ensures a user login will be terminated as soon as the "ClientAliveCountMax" is reached. |
| V-93991 | Low | The ESXi host SSH daemon must be configured to not allow gateway ports. | SSH TCP connection forwarding provides a mechanism to establish TCP connections proxied by the SSH server. This function can provide similar convenience to a Virtual Private Network (VPN) with the... |
| V-94021 | Low | The ESXi host must use Active Directory for local user authentication. | Join ESXi hosts to an Active Directory (AD) domain to eliminate the need to create and maintain multiple local user accounts. Using AD for user authentication simplifies the ESXi host... |
| V-94063 | Low | The ESXi host must enable BPDU filter on the host to prevent being locked out of physical switch ports with Portfast and BPDU Guard enabled. | BPDU Guard and Portfast are commonly enabled on the physical switch to which the ESXi host is directly connected to reduce the STP convergence delay. If a BPDU packet is sent from a virtual... |
| V-94007 | Low | The ESXi host must produce audit records containing information to establish what type of events occurred. | Without establishing what types of events occurred, it would be difficult to establish, correlate, and investigate the events leading up to an outage or attack. |
| V-94001 | Low | The ESXi hostSSH daemon must set a timeout interval on idle sessions. | Causing idle users to be automatically logged out guards against compromises one system leading trivially to compromises on another. |
| V-94027 | Low | The ESXi host must use multifactor authentication for local access to privileged accounts. | To assure accountability and prevent unauthenticated access, privileged users must utilize multifactor authentication to prevent potential misuse and compromise of the system. |
| V-94081 | Low | All ESXi host-connected physical switch ports must be configured with spanning tree disabled. | Since VMware virtual switches do not support STP, the ESXi host-connected physical switch ports must have portfast configured if spanning tree is enabled to avoid loops within the physical switch... |
