Forescout Network Access Control Security Technical Implementation Guide


This Security Technical Implementation Guide is published as a tool to improve the security of Department of Defense (DoD) information systems. The requirements are derived from the National Institute of Standards and Technology (NIST) 800-53 and related documents. Comments or proposed revisions to this document should be sent via email to the following address: [email protected]


Version / Release: V1R2

Published: 2021-09-27

Updated At: 2021-11-06 12:47:36

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High 0 0 0 0
Drop CKL or SCAP (XCCDF) results here.

    Vuln Rule Version CCI Severity Title Description Status Finding Details Comments
    SV-233309r803497_rule FORE-NC-000010 CCI-000213 HIGH Forescout must enforce approved access by employing admissions assessment filters that include, at a minimum, device attributes such as type, IP address, resource group, and/or mission conditions as defined in Forescout System Security Plan (SSP). Successful authentication must not automatically give an entity access to an asset or security boundary. The lack of authorization-based access control could result in the immediate compromise and unauthorized access to sensitive information. Authorizati
    SV-233310r803621_rule FORE-NC-000020 CCI-000213 HIGH Endpoint policy assessment must proceed after the endpoint attempting access has been identified using an approved identification method such as IP address. Automated policy assessments must reflect the organization's current security policy so entry control decisions will happen only where remote endpoints meet the organization's security requirements. If the remote endpoints are allowed to connect to the or
    SV-233311r803499_rule FORE-NC-000030 CCI-000213 HIGH For endpoints that require automated remediation, Forescout must be configured to redirect endpoints to a logically separate network segment for remediation services. Automated and manual procedures for remediation for critical security updates will be managed differently. Continuing to assess and remediate endpoints with risks that could endanger the network could impact network usage for all users. This isolation pre
    SV-233312r803500_rule FORE-NC-000040 CCI-000213 HIGH If a device requesting access fails Forescout policy assessment, Forescout must communicate with other components and the switch to either terminate the session or isolate the device from the trusted network for remediation. Endpoints with identified security flaws and weaknesses endanger the network and other devices on it. Isolation or termination prevents traffic from flowing with traffic from endpoints that have been fully assessed and authorized.
    SV-233313r615864_rule FORE-NC-000050 CCI-000213 MEDIUM Forescout must be configured to notify the user before proceeding with remediation of the user's endpoint device when automated remediation is used. Connections that bypass established security controls should be allowed only in cases of administrative need. These procedures and use cases must be approved by the Information System Security Manager (ISSM). This setting may be sent from the assessment
    SV-233314r803501_rule FORE-NC-000060 CCI-000213 HIGH Forescout must be configured so that all client machines are assessed by Forescout with exceptions that are allowed to bypass Forescout based on account or account type, as approved by the Information System Security Manager (ISSM) and documented in the System Security Plan (SSP). The NAC gateway provides the policy enforcement allowing or denying the endpoint to the network. Unauthorized endpoints that bypass this control present a risk to the organization's data and network.
    SV-233315r611394_rule FORE-NC-000070 CCI-000213 HIGH Forescout appliance must not be configured to implement a DHCP layer 3 method for separation or device authorization. An internal rogue device can still bypass the authentication process, regardless of the policy flow. Configuring the NAC to process all device authentication will ensure that any rogue device, internal or external, will be authenticated prior to network a
    SV-233316r611394_rule FORE-NC-000080 CCI-000213 MEDIUM Forescout must send an alert to the Information System Security Manager (ISSM) and System Administrator (SA), at a minimum, when critical security issues are found that put the network at risk. Requiring authentication and authorization of both the user's identity and the identity of the computing device is essential to ensuring a non-authorized person or device has entered the network.
    SV-233317r611394_rule FORE-NC-000090 CCI-000213 MEDIUM When devices fail the policy assessment, Forescout must create a record with sufficient detail suitable for forwarding to a remediation server for automated remediation or sending to the user for manual remediation. Notifications sent to the user and/or network administrator informing them of remediation requirements will ensure that action is taken.
    SV-233318r803502_rule FORE-NC-000100 CCI-000213 HIGH Forescout must place client machines on a blacklist or terminate network communications on devices when critical security issues are found that put the network at risk. This is . Devices that are found to have critical security issues place the network at risk if they are allowed to continue communications. Policy actions should be in place to terminate or restrict network communication or place the suspicious machine on a blackli
    SV-233319r611394_rule FORE-NC-000110 CCI-000213 MEDIUM Forescout must be configured so client machines do not communicate with other network devices in the DMZ or subnet except as needed to perform a client assessment or to identify itself. Devices not compliant with DoD secure configuration policies are vulnerable to attack. Allowing these systems to connect presents a danger to the enclave. Verify that Forescout is not allowed to communicate with other hosts in the DMZ that do not perfor
    SV-233320r803503_rule FORE-NC-000120 CCI-002178 MEDIUM Forescout must enforce the revocation of endpoint access authorizations when devices are removed from an authorization group. Ensuring the conditions that are configured in policy have proper time limits set to reflect changes will allow for proper access. This will help to validate that authorized individuals have proper access.
    SV-233321r803504_rule FORE-NC-000130 CCI-002179 MEDIUM Forescout must enforce the revocation of endpoint access authorizations at the next compliance assessment interval based on changes to the compliance assessment security policy. This requirement gives the option to configure for automated remediation and/or manual remediation. A detailed record must be passed to the remediation server for action. Alternatively, the details can be passed in a notice to the user for action. The dev
    SV-233322r803505_rule FORE-NC-000140 CCI-002179 MEDIUM Forescout must deny or restrict access for endpoints that fail critical endpoint security checks. Devices that do not meet minimum-security configuration requirements pose a risk to the DoD network and information assets. Endpoint devices must be disconnected or given limited access as designated by the approval authority and system owner if the devi
    SV-233323r611394_rule FORE-NC-000150 CCI-001844 MEDIUM Forescout must be configured to log records onto a centralized events server. Keeping an established, connection-oriented audit record is essential to keeping audit logs in accordance with DoD requirements.
    SV-233324r611394_rule FORE-NC-000160 CCI-001851 MEDIUM Forescout must off-load log records onto a different system. Having a separate, secure location for log records is essential to the preservation of logs as required by policy.
    SV-233325r615865_rule FORE-NC-000170 CCI-001858 MEDIUM Forescout must generate a critical alert to be sent to the Information System Security Officer (ISSO) and Systems Administrator (SA) (at a minimum) in the event of an audit processing failure. Ensuring that a security solution alerts in the event of misconfiguration or error is imperative to ensuring that proper auditing is being conducted. Having the ability to immediately notify an administrator when this auditing fails allows for a quick res
    SV-233326r803506_rule FORE-NC-000180 CCI-001958 MEDIUM Forescout must authenticate all endpoint devices before establishing a connection and proceeding with posture assessment. Authenticating all devices as they connect to the network is the baseline of a good security solution. This is especially important prior to posture assessment to ensure authorized devices are online and have the proper posture prior to accessing the prod
    SV-233327r803507_rule FORE-NC-000190 CCI-001958 MEDIUM Forescout must be configured to apply dynamic ACLs that restrict the use of ports when non-entity endpoints are connected using MAC Authentication Bypass (MAB). MAB is only one way of connecting non-entity endpoints, and can be defeated by spoofing the MAC address of an assumed authorized device. By adding the device to the MAR, the device can then gain access to the network. NPE devices that can support PKI or
    SV-233328r803508_rule FORE-NC-000210 CCI-001312 MEDIUM Forescout must reveal error messages only to the Information System Security Officer (ISSO), Information System Security Manager (ISSM), and System Administrator (SA). Ensuring the proper amount of information is provided to the Security Management staff is imperative to ensure role based access control. Only those individuals that need to know about a security error of an application need to be notified of the error.
    SV-233329r615867_rule FORE-NC-000230 CCI-000139 MEDIUM Forescout must configure TCP for the syslog protocol to allow for detection by the central event server if communications is lost. It is critical for the appropriate personnel to be aware if a system is at risk of failing to process audit logs as required. Without this notification, the security personnel may be unaware of an impending failure of the audit capability and system opera
    SV-233330r803509_rule FORE-NC-000240 CCI-001958 MEDIUM Forescout switch module must only allow a maximum of one registered MAC address per access port. Limiting the number of registered MAC addresses on a switch access port can help prevent a CAM table overflow attack. This type of attack lets an attacker exploit the hardware and memory limitations of a switch. If there are enough entries stored in a CAM
    SV-233331r803510_rule FORE-NC-000260 CCI-002361 MEDIUM For TLS connections, Forescout must automatically terminate the session when a client certificate is requested and the client does not have a suitable certificate. In accordance with NIST SP 800-52, the TLS server must terminate the connection with a fatal “handshake failure” alert when a client certificate is requested and the client does not have a suitable certificate. During the TLS handshake negotiation, a
    SV-233332r803511_rule FORE-NC-000270 CCI-000068 MEDIUM Forescout must use TLS 1.2, at a minimum, to protect the confidentiality of information passed between the endpoint agent and Forescout for the purposes of client posture assessment. Using older unauthorized versions or incorrectly configuring protocol negotiation makes the gateway vulnerable to known and unknown attacks that exploit vulnerabilities in this protocol.
    SV-233333r803512_rule FORE-NC-000280 CCI-000068 HIGH Forescout that stores device keys must have a key management process that is FIPS-approved and protected by Advanced Encryption Standard (AES) block cipher algorithms. The NAC that stores secret or private keys must use FIPS-approved key management technology and processes in the production and control of private/secret cryptographic keys. Private key data is used to prove that the entity presenting a public key certifi
    SV-233334r611394_rule FORE-NC-000290 CCI-002353 MEDIUM Communications between Forescout endpoint agent and the switch must transmit access authorization information via a protected path using a cryptographic mechanism. Forescout solution assesses the compliance posture of each client and returns an access decision based on configured security policy. The communications associated with this traffic must be protected from alteration and spoofing attacks so unauthorized de
    SV-233335r803513_rule FORE-NC-000340 CCI-000172 MEDIUM Forescout must generate a log record when the client machine fails policy assessment because required security software is missing or has been deleted. Generating log records with regard to modules and policies is an important part of maintaining proper cyber hygiene. Keeping and maintaining the logs helps to establish, correlate, and investigate the events relating to an incident, or identify those resp
    SV-233336r616547_rule FORE-NC-000420 CCI-001861 MEDIUM Forescout must be configured with a secondary log server, in case the primary log is unreachable. It is critical for the appropriate personnel to be aware if a system is at risk of failing to process audit logs as required. Without this notification, the security personnel may be unaware of an impending failure of the audit capability and system opera
    SV-233337r611394_rule FORE-NC-000440 CCI-000366 MEDIUM Forescout must perform continuous detection and tracking of endpoint devices attached to the network. Continuous scanning capabilities on the NAC provide visibility of devices that are connected to the switch ports. The NAC continuously scans networks and monitors the activity of managed and unmanaged devices, which can be personally owned or rogue endpoi
    SV-233338r803514_rule FORE-NC-000450 CCI-000778 MEDIUM Forescout must deny network connection for endpoints that cannot be authenticated using an approved method. Without identifying devices, unidentified or unknown devices may be introduced, thereby facilitating malicious activity. Identification failure does not need to result in connection termination or preclude compliance assessment. This is particularly true
    SV-233339r803515_rule FORE-NC-000460 CCI-001967 MEDIUM Forescout must use a bidirectional authentication mechanism configured with a FIPS-validated Advanced Encryption Standard (AES) cipher block algorithm to authenticate with the endpoint device. Bidirectional authentication provides stronger safeguards to validate the identity of other devices for connections that are of greater risk. Currently, DoD requires the use of AES for bidirectional authentication since it is the only FIPS-validated AES c
    SV-233340r803516_rule FORE-NC-000470 CCI-000185 HIGH When connecting with endpoints, Forescout must validate certificates used for Transport Layer Security (TLS) functions by performing RFC 5280-compliant certification path validation. A certificate's certification path is the path from the end entity certificate to a trusted root certification authority (CA). Certification path validation is necessary for a relying party to make an informed decision regarding acceptance of an end entit