Product Cybersecurity Guideline

09/2024 MZ049001EN

easyE4 has been designed with cybersecurity as an important consideration. A number of features areoffered in the product to address cybersecurity risks. These Cybersecurity Recommendations provide
information to help users to deploy and maintain the product in a manner that minimizes the cybersecurity
risks. These Cybersecurity Recommendations are not intended to provide a comprehensive guide tocybersecurity, but rather to complement customers’ existing cybersecurity programs.
Eaton is committed to minimizing the cybersecurity risk in its products and deploying cybersecurity bestpractices in its products and solutions, making them more secure, reliable, competitive for customers.

Category

Description[1] Intended Use &Deployment Context

The easyE4 shall be used as a control relay in various industrial and building
applications. The easyE4 base unit can be expanded by I/O modules through theeasyConnect bus, by a SWD network through the SWD coordinator
EASY-COM-SWD-C1 and through the communication module
EASY-COM-RTU-M1 by a network of Modbus RTU devices.
The easyE4 base unit and I/O devices as well as communication devices
EASY-COM-SWD-C1 and EASY-COM-RTU-M1 are typically mounted in control
cabinets, control panels, service distribution boards, or control consoles.
Before deployment the easyE4 base unit needs to be configured through theeasySoft software tool or through a pre-defined easySoft project stored on a SD
card. The SWD coordinator EASY-COM-SWD-C1 and Modbus RTU
EASY-COM-RTU-M1 can only be configured through the easyE4 base unit.
After deployment the easyE4 either has no permanent connection to an Ethernet
network or shall be used in protected ethernet network zone only.
The SWD coordinator EASY-COM-SWD-C1 and Modbus RTU
EASY-COM-RTU-M1 cannot be connected to an Ethernet network but only to theeasyE4 base unit through the EASY-E4-CONNECT-COM1 connector and to the
SWD network through the standard SWD flat ribbon cable, and to the Modbus
network through RS485 serial cable.

[2] Asset
Management

Keeping track of software and hardware assets in your environment is a prerequisite for effectively managing cybersecurity. Eaton recommends that you
maintain an asset inventory that uniquely identifies each important component. To
facilitate this, easyE4 supports the following identifying information:
The printings on the easyE4 enclosure include manufacturer including location,
type ID and Ethernet MAC-ID. The QR code of devices manufactured before
04/2024 contains the serial number, firmware version number (at time of
production) and a link to product documentation. The QR code of devices
manufactured from 04/2024 can be used with the Eaton Asset Manager App formobile phones for a more convenient asset management.
This information can also be retrieved through device display itself, easySoft andweb client (if activated).
The printing on the EASY-COM-SWD-C1 and EASY-COM-RTU-M1 enclosure
include manufacturer including location, type ID, firmware version number (at timeof production) as part of the QR code.
This information can also be retrieved through the easySoft.
For details see device and easySoft manual at Download Center Documentation
easyE4 manual, MN050009.

Category[3] Defense in Depth[4] Risk Assessment[5] Physical Security

Description
Defense in Depth basically means applying multiple counter-measures for
mitigating risks, in a layered or step wise manner. A layered approach to security
as shown in the below diagram is what is recommended. Defense in Depth is the
responsibility of both the manufacturer and the customer.

Eaton recommends conducting a risk assessment to identify and assess
reasonably foreseeable internal and external risks to the confidentiality,
availability and integrity of the system | device and its environment. This exercise
should be conducted in accordance with applicable technical and regulatory
frameworks such as IEC 62443 and NERC-CIP. The risk assessment should be
repeated periodically.
An attacker with unauthorized physical access can cause serious disruption tosystem/device functionality. Additionally, Industrial Control Protocols don’t offer
cryptographic protections, making ICS and SCADA communications especiallyvulnerable to threats to their confidentiality. Physical security is an importantlayer of defense in such cases. easyE4 is designed to be deployed and operated
in a physically secure location. Following are some best practices that Eaton
recommends to physically secure your system/device:
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Secure the facility and equipment rooms or closets with access control
mechanisms such as locks, entry card readers, guards, man traps, CCTV,
etc. as appropriate.
Restrict physical access to cabinets and/or enclosures containing easyE4,
EASY-COM-SWD-C1, EASY-COM-RTU-M1, attached expansions and theassociated system. Monitor and log the access at all times.
Physical access to the communication lines and network cabling should be
restricted to protect against attempts to intercept or sabotage
communications. It’s a best practice to use metal conduits for the network
cabling running between equipment cabinets.
Utilize additional physical access restriction mechanisms such as locks, card
readers, and/or guards etc. as appropriate.
easyE4 supports the following physical access ports: Ethernet port, SD card
slot. Access to these ports should be restricted.
Do not insert a SD card for any operation (e.g., firmware upgrade,
configuration change, or user program change) unless the origin of the media
is known and trusted.

Category

Description•[6] COTS Platform
Security

Before inserting a SD card, ensure that no malicious easyE4 program orunauthorized easyE4 firmware is stored on the SD card.

Eaton recommends that customers harden third-party commercial off-the-shelf(COTS) operating systems or platforms that are used to run Eaton applications /products (e.g., third party hardware, operating systems and hypervisors, such as
those made available by Dell, Microsoft, VMware, Cisco, etc.).
••

Eaton recommends that customers refer to the COTS vendor’s
documentation for guidance on how to harden these components.
Vendor-neutral guidance is made available by the Center for Internet Security
https://www.cisecurity.org/

Irrespective of the platform, customers should consider the following bestpractices:
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[7] AccountManagement

Install all security updates made available by the COTS manufacturer.
Change default credentials upon first login.
Disable or lock unused built-in accounts.
Limit use of privileged generic accounts (e.g., disable interactive login).
Change default SNMP community strings.
Restrict SNMP access using access control lists.
Disable unneeded ports & services.

Logical access to the device should be restricted to legitimate users, who should
be assigned only the privileges necessary to complete their job roles/functions.
Some of the following best practices may need to be implemented byincorporating them into the organization’s written policies:
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No password sharing – If you activate the webserver users admin, user1
and/or user2 make sure each user group gets its own password instead ofsharing the passwords across groups. Security monitoring/logging features in
the product are designed based on each user group having a uniquepassword. Allowing users to share credentials weakens security.
Restrict administrative privileges - Attackers seek to gain control of legitimate
credentials, especially those for highly privileged accounts. Administrative
privileges should be assigned only to accounts specifically designated foradministrative duties and not for regular use.
Leverage the roles / access privileges for the webserver users user1 anduser2 to provide tiered access to the users as per the business /operational
need. Follow the principle of least privilege (allocate the minimum authority
level and access to system resources required for the role).
Perform periodic account maintenance (remove unused accounts).
Enforce session time-out after a period of inactivity.
Set an easyE4 device password before commissioning. If the easyE4
webserver is activated the easySoft configuration dialog enforce a web
administrator password with proper password length and complexity.
In the easyE4 web client the admin user can create API keys with theprivileges of either user1 or user2. These keys are useful for the end user tomanage the access to the web API. Please ensure that each system,
application, or user uses an own API key instead of sharing the key.
Access to the device via easySoft does not provide different user roles. The
device password should be used to prevent unauthorized access to thedevice. Per default no device password is set. It is highly recommended to
set a device password in your easySoft project and activate it for all security
areas critical to the application.
The webserver offers three different users: admin, user1 and user2. The user
management is defined in the easySoft in the project settings. Accessprivileges for user1/user2 can be defined differently. In this way access to an
easyE4 controlling machinery can be organized as follows:Category

Description
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[8] Time
Synchronization

admin: access is limited to machine vendor and trained personnel of theend user company.
•“user1”: access can be limited to maintenance personnel.
•“user2”: access can be granted for machine operators.
The webserver allows concurrent login with the same user to allow different
persons access through one user role. Make sure that the password islimited to authorized personnel only.
The device menu can only be used with one (physical or virtual) device
display at a time. In this way concurrent logins cannot be used to read thedevice password.
When registering easyE4 with AWS IoT Core the following credentials areneeded for authentication:•
AWS access key ID•
AWS secret access key•
AWS session token
These AWS credentials need to be valid for the AWS registration process
only and are not stored permanently in the easyE4.

Many operations in power grids and IT networks heavily depend on precise timing
information.
Ensure the system clock is synchronized with an authoritative time source.
The easyE4 offers different options to synchronize system time: SNTP, radio
clock (DCF), easyNET and manually through easySoft (for instructions see
manuals).

[9] Network Security

easyE4 supports network communication with other devices in the environment.
This capability can present risks if it’s not configured securely. Following are
Eaton recommended best practices to help secure the network. Additional
information about various network protection strategies is available in Eaton
Cybersecurity Considerations for Electrical Distribution Systems [R1].
Eaton recommends segmentation of networks into logical enclaves, denying
traffic between segments except that which is specifically allowed, and restricting
communication to host-to-host paths (for example, using router ACLs and firewall
rules). This helps to protect sensitive information and critical services and creates
additional barriers in the event of a network perimeter breach. At a minimum, autility Industrial Control Systems network should be segmented into a three-tiered
architecture (as recommended by NIST SP 800-82[R3]) for better security control.
Deploy adequate network protection devices like Firewalls, Intrusion Detection /Protection devices.
Communication Protection: easyE4 provides the option to encrypt its network
communications. Please ensure that encryption options are enabled. You cansecure the product’s communication capabilities by taking the following steps:••

easyE4 provides the option to encrypt the n/w traffic for the webserver(HTTPS) and for sending e-mails (SMTPS). Deactivation of this encryption is
on your own liability. Therefore, please ensure that encryption options are notdisabled.
For the webserver use the encryption if your http client supports it and if you
are using at least the easyE4 hardware V8 and at least firmware V2.00.
Starting with easyE4 hardware V8 easyE4 supports TLS1.2 with a certificate
signed by easyE4 itself. It is not part of a chain of trust connected to a CA (onopen internet). The root certificate installed by easySoft will ensure that thebrowser is communicating with a product family easyE4 device, without
identifying a dedicated easyE4 device. This authentication is established withlevels of certificates inside the device. It is recommended to use https insteadCategory

Description

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of http to protect the http n/w traffic against monitoring password etc., even if
you are using an older easyE4 hardware than V8 and therefore facing a web
browser warning because of a self-signed certificate.
For a faster user experience when using the web-client we recommend using
Google Chrome or Microsoft Edge since these browsers support TLS session
resumption through TLS tickets.
For e-mails (SMTPS) use as encryption options either STARTTLS or
TLS/SSL if the e-mail server allows one of these options. If no encryption isused for sending e-mails the device will automatically switch to STARTTLS if
the e-mail server supports this.
For both options TLS version 1.2 is used.
For SMTPS the following TLS cipher suites are supported:•
TLS_RSA_WITH_AES_128_CBC_SHA,•
TLS_RSA_WITH_AES_256_GCM_SHA384,•
TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA,•
TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256,•
TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA,•
TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,•
TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256,•
TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,•
TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA.
Please find detailed information about various Network level protection
strategies in Eaton Cybersecurity Considerations for Electrical Distribution
Systems [R1]. Use the below information for configuring the firewalls to allow
needed access for easyE4 to operate smoothly.
•https (default port 443): The webserver can be activated and configured
in easySoft. The default setting use https (TLS) and port 443. The port
can be changed to suit the situation of the local network. Only activate
the webserver if needed. The webserver can be started during device
boot-up or the user can switch the webserver on/off during execution of
the easySoft user program, For the latter option use the function block
alarm. Utilizing these options, the webserver can be activated in case ofmaintenance incidents only.
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http (default port 80): The webserver can be configured to be usedwithout encryption. In this case port 80 is the default port. The
recommendation is to always use https instead of http.
•easySoft (default port 443, 80 or 10001): The communication with
easySoft can be established using 3 different options.
o Option a) Use easyCOM v2 encrypted based on ws/TLS(standard port 443) (default option)o Option b) Use easyCOM v2 unencrypted based on ws(standard port 80) (not recommended)o Option c) Use easyCOM v1 unencrypted based on TCP(standard port 10001) (not recommended)
The default option a) uses TLS based encryption. The port can bechanged to suit the situation of the local network. Since thecommunication using option b) or c) is not encrypted, the device
should in these cases only be used in a secure network
environment.
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Modbus TCP Server (port 502): The Modbus TCP server/slavefunctionality can be activated in easySoft. The port number cannot bechanged. Since every Modbus TCP client can connect to the server thedevice should only be used in a secure network environment.
easyNET (port range 10100 to 10110): Port range used by the NET
protocol dedicated for controller-to-controller between easy devices.
easyNET should only be used in a secure network environment.
Discover (UDP port 11111): Discovery service for device identification.
The device delivers information about itself on request.
easyE RTD (ports 11112, 11113 and 11119):Category

Description
port 11112: Used to communicate the easyE4’s display content
to an easyE RTD and key events in the other direction. The
UDP communication is protected by a cryptographic hash. The
communication should only be operated in a secure network
environment. The usage of this port can be disabled in easySoft
by setting the “Remote display configuration” in the Ethernet tab
to “No access”. It is disabled as default.
o Port 11113: Used to communicate customized visualization
content between easyE4 and easyE RTDs. The UDP
communication is protected by a cryptographic hash. The
communication should only be operated in a secure network
environment. The usage of this port can be disabled in easySoft
by unchecking the “Allow visualization” in the Ethernet tab. It isdisabled as default.
o Port 11119: TLS protected service to open a display session
and/or visualization communication in easyE4 for easy Remote
Touch Display. This can be disabled by disabling both functions(port 11112 and 11113) above.
AWS device registration (standard https port 443): The AWS device
registration is required before establishing a connection to AWS IoT
Core.
Project download from AWS S3 (https port 443): easyE4 can download a
project file from AWS S3 as part of the project update via cloud process.
The connection to the AWS IoT server uses MQTT, where easyE4 acts
as the MQTT client. The default ports for AWS IoT Core communication
are:o ALPN activated: TLS port 443 with ALPN protocol name “xamzn-mqtt-ca”,
o ALPN deactivated: standard MQTT port 8883.
AWS IoT Core uses mutual certificate authentication. Therefore, MQTT
connection to AWS cannot be established when using a proxy server,which exchanges the certificate for the AWS communication.
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Note: Many compliance frameworks and cybersecurity best practices require an
audit of ports and services before and after applying updates and systemchanges. An end user should be able to refer to the ports and services
documentation to determine the expected minimal set of ports and services on a
device.
[10] Remote Access

Remote access to devices/systems creates another entry point into the network.
Strict management and validation of termination of such access is vital for
maintaining control over overall ICS security.
The easy devices should only be used inside a secure network environment.
Remote access to the device should only be possible through securetechnologies like virtual private networks.
Each web session uses a timeout of 30 seconds to determine if a web client is stillconnected. If no life-signal from the web client is received within this period, thesession is closed.
The easySoft communication to the device does not use timeout settings since it
might be requested to keep a connection open for a longer time to perform
debugging of a user application. This should only be used inside a secure
network environment. To ensure no malicious access don’t leave your workstation
unlocked while easySoft is connected to the device.
For further recommendations please read Security best practices checklist.

[11] Logging andEvent Management•

Eaton recommends logging all relevant system and application events,
including all administrative and maintenance activities.

Category

Description••••

Logs should be protected from tampering and other risks to their integrity (forexample, by restricting permissions to access and modify logs, transmitting
logs to a security information and event management system, etc.).
Ensure that logs are retained for a reasonable and appropriate length of time.
Review the logs regularly. The frequency of review should be reasonable,
taking into account the sensitivity and criticality of the system | device andany data it processes.
easyE4 offers logging of system events on SD card. This functionality can be
activated in the system settings of the easySoft project. The log files contain
event codes and a time stamp. The following table lists all event codes of theeasyE4:
Event code

Description0

Program download from eS7

1

Program download from SD

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Program deletion

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Web API key created

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Wrong web API key entered5

New device password created6

Device password deleted

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Wrong device password entered

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SWD config. button pressed9

Firmware update of easyConnect device

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Firmware update of ComBUS device

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Firmware update base device

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Web user: Invalid user or Password

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FW update base device started

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FW update base device signature invalid

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FW update base device failed (e.g. update for wrong device)Category[12] Vulnerability
Scanning

Description

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Project update via cloud started

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Project update via cloud failed

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Project update via cloud successful

120

Modbus TCP Client activated121

Modbus TCP Client deactivated122

Modbus TCP Client: configuration changed

123

Modbus TCP Client: invalid data received

To utilize easyE4 and easySoft it is needed to install and use third-party software
like Windows or web browsers. Any known critical or high severity vulnerabilities
on third party component/libraries should be remediated before putting the system
into production.
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Eaton recommends running a vulnerability scan to identify known
vulnerabilities for software used with the product. For COTS components(e.g., applications running on Windows), vulnerabilities can be tracked on the
National Vulnerability Database (NVD), available at https://nvd.nist.gov/.
Keep software updated by monitoring security patches made available by
COTS vendors and installing them as soon as possible.

Note: Many compliance frameworks and security best practices require a monthly
vulnerability review. For many non-COTS products vulnerabilities will be
communicated directly through the vendor site.
[13] Malware
DefensesEaton recommends deploying adequate malware defenses to protect the productor the platforms used to run the Eaton product.

[14] Secure
MaintenanceThe device includes a web client to allow a service engineer to retrieve
information from an easyE4 device which includes:••••

active easyE4 diagnostic IDs,
easyE4 diagnostic buffer entries,
network settings,
SMTP settings.

Best Practices
Update device firmware prior to putting the device into production. Thereafter,
apply firmware updates and software patches regularly.
Eaton publishes patches and updates for its products to protect them against
vulnerabilities that are discovered. Eaton encourages customers to maintain aconsistent process to promptly monitor for and install new firmware updates.

Category

Description•

A firmware update file can be downloaded from the Eaton website. This file
has to be copied on a SD card and selected in the device menu. The device
must be rebooted with the SD card plugged in (see device manual for
instructions).

Please check Software Download Center for information bulletins about available
firmware and software updates.
[15] BusinessContinuity /Cybersecurity
Disaster Recovery

Plan for Business Continuity / Cybersecurity Disaster Recovery
Eaton recommends incorporating easyE4 into the organization’s business
continuity and disaster recovery plans. Organizations should establish a
Business Continuity Plan and a Disaster Recovery Plan and should periodicallyreview and, where possible, exercise these plans. As part of the plan, importantsystem | device data should be backed up and securely stored, including:•••

Backup of the latest firmware for easyE4. Make it a part of standard
operating procedure to update the backup copy as soon as the latest
firmware is updated.
Backup of the most current easySoft project.
Documentation of the most current user list.

The following section describes the details of failures states and backup
functions:
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[16] Customer
Application Security

If a firmware update of the easyE4 base unit fails, the LCD will show 60
seconds after power-on a red backlight color and the word "error". Solution:
Restart the base device with a valid firmware update file on the SD card. If
the firmware update fails again, please contact the support.
The ETH LED indicates Ethernet and easyNET status. On devices with LCD
these statuses are shown on the start display. For details see device manual.
The power LED of the easyE4 indicates operation mode (STOP/RUN) andcommunication status to the IO extension modules (if configured). On
devices with LCD this information is shown on the start display.
The power LED of the EASY-COM-SWD-C1 and EASY-COM-RTU-M1
indicates operation mode (STOP/RUN) and communication status to theeasyE4 base unit. In case the firmware update of the EASY-COM-SWD-C1
or EASY-COM-RTU-M1fails the power LED will blink green with 5Hz.
Solution: Try to update the device with a valid firmware again, check if the
update file on the SD card is broken. If the firmware update fails again pleasecontact the support. For further details see device manual.

easyE4 provides a platform on which customers can customize and hostapplications according to their requirements. This especially applies toapplications using the easyE4 JSON API. Security vulnerabilities in theseapplications may expose the underlying device to attack.
Eaton recommends observing best practices for secure system development
when customers develop and host an application on the device:••

Privacy and Security by Design: The application should take security andprivacy into consideration from the outset, including at the stage of defining
requirements and assessing the associated risks.
Communication Protection: If the application communicates over the
network, Eaton recommends encrypting the communications in accordancewith the applicable level described by the FIPS 140-2 standard.
o easyE4 provides option to protect the interface to easySoft by thedevice password. This option should be activated always.

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Description
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[17] Sensitive
Information
Disclosure0.

easyE4 provides option to encrypt communication to easySoft(easyProtocol V2). It is recommended to always activate thisfeature.
o easyE4 provides option to encrypt webserver communication(https). It is recommended to always activate this feature.
o easyE4 provides option to restrict the access to operands via thewebserver. Only the necessary operands shall be exposed via thewebserver.
Always secure the easySoft project with a password (as described in
easySoft manual).
Access Enforcement: The application should provide the ability to enforce
access controls to protect the application against unauthorized access and toprotect accounts against unauthorized authentication attempts (for example,
through account lockout).
Least Privilege: easyE4 provides option to restrict the webserver access tothe users admin, user1 and user2. It is recommended to not allow
anonymous access.
Input Checking: All input to the application should be sanitized before storingand processing by the application to protect against malicious code injection.
Output Handling: Data output by the application for user consumption,
including error messages, should be appropriately handled to avoid revealing
important information about the application and the underlying system. The
application should generate sufficient error message to diagnose any issue inthe application but shouldn’t reveal useful information that can be exploitedby malicious users.
Password Management: The application should securely store and transmit
credentials (for example, encrypting authentication traffic, and salting andhashing passwords in transit and at rest). Password complexity should be
implemented, and password should be masked when entered on-screen.
Secure Coding Practices: Follow secure coding practice while developing
applications for the device (for example, implementing multiple security
layers, verifying authorization for all requests, conducting code reviews, etc.).
Administration Interface: The interface for administering the application
should be separated from the end-user interface.
Session Controls: All application sessions should be encrypted, logged andmonitored.
Event Log Generation: The application should have the capability to log
security related events at a minimum, including the time, date, and user.
When project update via cloud (AWS) is activated/allowed, an Update ID
shall be set in easyE4. This Update ID must be set once in device by aspecial web API call and every time when a project (dedicated for update via
cloud) is exported by easySoft. The project will be discarded in case of amismatch of the update ID in device and in project file. The Update ID has tobe kept secret.

Eaton recommends that sensitive information (i.e. connectivity, log data, personal
information) that may be stored by easyE4 be adequately protected through the
deployment of organizational security practices.

Category

Description[18]
Decommissioning or
Zeroization

It is a best practice to purge data before disposing of any device containing data.
Guidelines for decommissioning are provided in NIST SP 800-88. Eaton
recommends that products containing embedded flash memory be securely
destroyed to ensure data is unrecoverable.

* Figure and data from NIST SP800-88
Embedded Flash Memory on Boards and Devices
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Eaton recommends the following methods for disposing of motherboards,
peripheral cards such as network adapters, or any other adapter containing
non-volatile flash memory.
Clear: If supported by the device, reset the state to original factory settings.
The easyE4 supports a factory reset through a dedicated file on the SD card.
The reset will also delete the AWS certificate and the Update ID (used for
project updates via cloud).
In addition, it is possible to delete the user program in the device menu andthrough easySoft (see device manual for instructions).
Purge: If the flash memory can be easily identified and removed from theboard, the flash memory may be destroyed independently of the board that
contained the flash memory. Otherwise, the whole board should bedestroyed. The SD card of easyE4 can be removed from the device anddestroyed separately. The internal flash memory should be destroyed as partof the whole board.
Destroy: Shred, disintegrate, pulverize, or incinerate by burning the device ina licensed incinerator.

[R1] Cybersecurity Considerations for Electrical Distribution Systems (WP152002EN):
http://www.eaton.com/ecm/groups/public/@pub/@eaton/@corp/documents/content/pct_1603172.pdf[R2] Cybersecurity Best Practices Checklist Reminder (WP910003EN):
https://www.eaton.com/content/dam/eaton/company/news-insights/cybersecurity/white-papers/WP910003EN.pdf[R3] NIST SP 800-82 Rev 2, Guide to Industrial Control Systems (ICS) Security, May 2015:
https://nvlpubs.nist.gov/nistpubs/SpecialPublications/NIST.SP.800-82r2.pdf[R4] National Institute of Technology (NIST) Interagency “Guidelines on Firewalls and Firewall Policy, NIST Special
Publication 800-41”, October 2009: http://nvlpubs.nist.gov/nistpubs/Legacy/SP/nistspecialpublication800-41r1.pdf[R5] NIST SP 800-88, Guidelines for Media Sanitization, September 2006:
http://ws680.nist.gov/publication/get_pdf.cfm?pub_id=50819[R6] A Summary of Cybersecurity Best Practices - Homeland Security
https://www.hsdl.org/?view&did=806518