Trellix Application Control 8.x Security Technical Implementation Guide

Overview

Version	Date	Finding Count (31)			Downloads
3	2025-06-09	CAT I (High): 2	CAT II (Medium): 29	CAT III (Low): 0	Excel JSON XML

Stig Description

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: disa.stig_spt@mail.mil.

Classified	Public	Sensitive
I - Mission Critical Classified	I - Mission Critical Public	I - Mission Critical Sensitive	II - Mission Critical Classified	II - Mission Critical Public	II - Mission Critical Sensitive	III - Mission Critical Classified	III - Mission Critical Public	III - Mission Critical Sensitive

Findings - MAC I - Mission Critical Classified

Finding ID	Severity	Title	Description
V-213328	High	The Solidcore client Command Line Interface (CLI) Access Password must be changed from the default.	The Solidcore client can be configured locally at the CLI, but only when accessed with the required password. Since the Trellix Application Control configuration is to be managed by ePO policies, allowing enablement of the CLI to would introduce the capability of local configuration changes. Strict management of the accessibility...
V-213327	High	The Solidcore client Command Line Interface (CLI) must be in lockdown mode.	By default, when an endpoint's Solidcore installation is managed by the ePO server, the CLI will automatically be in lockdown mode. This will ensure the endpoint receives all of its Solidcore configuration settings from the ePO server. The CLI can, however, be activated for troubleshooting efforts during which time the...
V-213347	Medium	The Solidcore Client Exception Rules must be documented in the organizations written policy.	When exceptions are created for applications, it results in potential attack vectors. As such, exceptions should only be created with a full approval by the local ISSO/ISSM. The organization's entire written policy requires approval by the ISSO/ISSM/AO and is required to be under CAB/CCB oversight.
V-213346	Medium	The Throttling settings must be enabled and configured to settings according to organizations requirements.	The throttling settings regulate the data flow between the clients and Trellix ePO. The value for each category defines the number of entries that will be sent to the Trellix ePO daily. Clients start caching for the defined category when the specified threshold value is reached. After the cache is...
V-213345	Medium	The organization-specific Solidcore Client Policies must be created and applied to all endpoints.	Trellix Application Control is deployed with default policies. To ensure the default policies are not used and that an organization knowingly configures their systems to their own configuration requirements, organization-specific policies will need to be created.
V-213344	Medium	The organization-specific Rules policies must be part of the effective rules policy applied to all endpoints.	To ensure Solidcore clients are only configured to STIG and organization-specific settings, an organization-specific ePO policies must be applied to all organization workstation endpoints. The Trellix Application Control installs with two Default Rules policies. The Trellix Default Rules policy includes the whitelist for commonly used applications to the platform. The...
V-213343	Medium	A copy of the Trellix Default Rules policy must be part of the effective rules policy applied to every endpoint.	To ensure Solidcore clients are only configured to STIG and organization-specific settings, an organization-specific ePO policies must be applied to all organization workstation endpoints. The Trellix Application Control installs with two Default Rules policies. The Trellix Default Rules policy includes the whitelist for commonly used applications to the platform. The...
V-213342	Medium	The Trellix Applications Default Rules policy must be part of the effective rules policy applied to every endpoint.	To ensure Solidcore clients are only configured to STIG and organization-specific settings, organization-specific ePO policies must be applied to all organization workstation endpoints. The Trellix Application Control installs with two Default Rules policies. The Trellix Default Rules policy includes the whitelist for commonly used applications to the platform. The Trellix...
V-213341	Medium	The Trellix Application Control Options Inventory interval option must be configured to pull inventory from endpoints on a regular basis not to exceed seven days.	When Trellix Application Control is deployed on a system, it creates a whitelist of all executable binaries and scripts present on the system. The whitelist contains all authorized files, and only files that are present in the whitelist are allowed to execute. An executable binary, script, or process that is...
V-213340	Medium	The Trellix Application Control Options Inventory option must be configured to hide OS Files.
V-213339	Medium	Enabled features under Trellix Application Control Options policies Enforce feature control must not be configured unless documented in written policy and approved by ISSO/ISSM.	By default, the Trellix Application Control prevents installation of ActiveX controls on endpoints, enforces memory protection techniques on endpoints, and prevents MSI-installers from running on endpoints. The "Feature Control" allows for those safeguards to be bypassed and in doing so renders the Trellix Application Control less effective.
V-213338	Medium	The Trellix Application Control Options policies Enforce feature control memory protection must be enabled.	By default, the Trellix Application Control prevents installation of ActiveX controls on endpoints, enforces memory protection techniques on endpoints, and prevents MSI-installers from running on endpoints. The Feature Control allows for those safeguards to be bypassed and in doing so renders the Trellix Application Control less effective. Because ENS and...
V-213337	Medium	The Trellix Application Control Options policy End User Notification, if configured by organization, must have all default variables replaced with the organization-specific data.	The "User Message" option will show a dialog box when an event is detected and display the organization-specified text in the message.
V-213336	Medium	The Trellix Application Control Options policy must be configured to disable Self-Approval.	The Trellix Application Control Self-Approval feature allows the user to take an action when a user tries to run a new or unknown application.
V-213334	Medium	The Trellix Application Control Options Advanced Threat Defense (ATD) settings, if being used, must be configured to only send binaries with a size of 5MB or less.	Since binaries can be large, the file size must be limited to avoid congestion on the network and degradation on the endpoint when sending the binaries to the ATD.
V-213333	Medium	The Trellix Application Control Options Advanced Threat Defense (ATD) settings, if being used, must be configured to send all binaries with a reputation of Might be Trusted and below for analysis.	When the file reputation of "Might be Trusted" is configured for being forwarded to ATD, all files with the reputation of "Might be Trusted", "Unknown", "Might be Malicious", "Most Likely Malicious" and "Known Malicious" are forwarded to the ATD. The files with "Might be Trusted" reputation may be redesignated as...
V-213332	Medium	The Trellix Application Control Options Advanced Threat Defense (ATD) settings must not be enabled unless an internal ATD is maintained by the organization.	This option will automatically send files with a specific file reputation to ATD for further analysis. This option is not selected by default and must only be selected if an ATD is being used.
V-213331	Medium	The Trellix Application Control Options Reputation-Based Execution settings, if enabled, must be configured to allow Most Likely Trusted or Known Trusted only.	When a file is executed on an endpoint, the Application Control performs multiple checks to determine whether to allow or ban the execution. Only files with a reputation of "Most Likely Trusted", "Known Trusted" or "Might be Trusted" are considered to be allowed. By configuring the setting to only "Most...
V-213330	Medium	The Trellix Application Control Options Reputation setting must be configured to use the Trellix Global Threat Intelligence (Trellix GTI) option.	If a Threat Intelligence Exchange (TIE) server is being used in the organization, reputation for files and certificates is fetched from the TIE server. The reputation values control execution at endpoints and are displayed on the Application Control pages on the Trellix ePO console. If the GTI is being used,...
V-213329	Medium	The organization-specific Rules policy must only include executable and dll files that are associated with applications as allowed by the organizations written policy.	To ensure Solidcore clients are only configured to STIG and organization-specific settings, organization-specific ePO policies must be applied to all organization workstation endpoints. The Trellix Application Control installs with two Default Rules policies. The Trellix Default Rules policy includes the whitelist for commonly used applications to the platform. The Trellix...
V-213326	Medium	The Solidcore client must be enabled.	The Application Control whitelisting must be enabled on all workstation endpoints. To enable Application Control, the Solidcore client needs to be in enabled mode.
V-213325	Medium	The organizations written policy must include procedures for how often the whitelist of allowed applications is reviewed.	Enabling application whitelisting without adequate design and organization-specific requirements will either result in an implementation which is too relaxed or an implementation which causes denial of service to its user community. Documenting the specific requirements and trust model before configuring and deploying the Trellix Application Control software is mandatory.
V-213324	Medium	The organizations written policy must include a process for how whitelisted applications are deemed to be allowed.	Enabling application whitelisting without adequate design and organization-specific requirements will either result in an implementation which is too relaxed or an implementation which causes denial of service to its user community. Documenting the specific requirements and trust model before configuring and deploying the Trellix Application Control software is mandatory.
V-213323	Medium	The configuration of features under Trellix Application Control Options policies Enforce feature control must be documented in the organizations written policy.	By default, the Trellix Application Control prevents installation of ActiveX controls on endpoints, enforces memory protection techniques on endpoints, and prevents MSI-installers from running on endpoints. The Feature Control allows for those safeguards to be bypassed and in doing so renders the Trellix Application Control less effective.
V-213322	Medium	The Trellix Application Control Options Advanced Threat Defense (ATD) settings, if being used, must be confined to the organizations enclave.	Data will be leaving the endpoint to be analyzed by the ATD. Because data could feasibly be intercepted en route, risk of outside threats is minimized by ensuring the ATD is in the same enclave as the endpoints.
V-213321	Medium	The process by which the Solidcore client Command Line Interface (CLI) Access Password is made available to administrators when needed must be documented in the organizations written policy.	The Solidcore client can be configured locally at the CLI, but only when accessed with the required password. Since the Trellix Application Control configuration is to be managed by ePO policies, allowing enablement of the CLI to would introduce the capability of local configuration changes. Strict management of the accessibility...
V-213320	Medium	The requirement for scheduled Solidcore client Command Line Interface (CLI) Access Password changes must be documented in the organizations written policy.	The Solidcore client can be configured locally at the CLI, but only when accessed with the required password. The misuse of the CLI would open the system up to the possible configuration, allowing malicious applications to execute unknowingly. Strict management of the accessibility of the CLI is necessary in order...
V-213319	Medium	The Solidcore client Command Line Interface (CLI) Access Password protection process must be documented in the organizations written policy.	The Solidcore client can be configured locally at the CLI, but only when accessed with the required password. Since the Trellix Application Control configuration is to be managed by ePO policies, allowing enablement of the CLI to would introduce the capability of local configuration changes. Strict management of the accessibility...
V-213318	Medium	The Solidcore client Command Line Interface (CLI) Access password complexity requirements must be documented in the organizations written policy.	The Solidcore client can be configured locally at the CLI, but only when accessed with the required password. The misuse of the CLI would open the system up to the possible configuration, allowing malicious applications to execute unknowingly. Strict management of the accessibility of the CLI is necessary in order...
V-213317	Medium	The use of a Solidcore 8.x local Command Line Interface (CLI) Access Password must be documented in the organizations written policy.	The Solidcore client can be configured locally at the CLI, but only when accessed with the required password. Since the Trellix Application Control configuration is to be managed by ePO policies, allowing enablement of the CLI to would introduce the capability of local configuration changes. Strict management of the accessibility...
V-213316	Medium	A Trellix Application Control written policy must be documented to outline the organization-specific variables for application whitelisting.	Enabling application whitelisting without adequate design and organization-specific requirements will either result in an implementation which is too relaxed or an implementation which causes denial of service to its user community. Documenting the specific requirements and trust model before configuring and deploying the Trellix Application Control software is mandatory.