Document ID: NHTSA-2020-0087-0047
Agency: nhtsa
Document Type: Notice
Title: Cybersecurity Best Practices for the Safety of Modern Vehicles
Posted Date: 2022-09-09T04:00Z

[Federal Register Volume 87, Number 174 (Friday, September 9, 2022)]
[Notices]
[Pages 55459-55465]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2022-19507]

[[Page 55459]]

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DEPARTMENT OF TRANSPORTATION

National Highway Traffic Safety Administration

[Docket No. NHTSA-2020-0087]

Cybersecurity Best Practices for the Safety of Modern Vehicles

AGENCY: National Highway Traffic Safety Administration (NHTSA), 
Department of Transportation (DOT).

ACTION: Notice of federal guidelines.

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SUMMARY: On January 12, 2021, NHTSA released its draft Cybersecurity 
Best Practices for the Safety of Modern Vehicles guidance (``Draft Best 
Practices'' or ``guidance'') in an effort to support industry-led 
efforts to improve the industry's cybersecurity posture as well as 
provide NHTSA's views on how the automotive industry can develop and 
apply sound, risk-based cybersecurity management processes during the 
vehicle's entire lifecycle. These guidelines are intended to be 
applicable to all individuals and organizations involved in the design, 
development, manufacture and assembly of a motor vehicle and its 
electronic systems and software. These entities include, but are not 
limited to, small and large-volume motor vehicle and motor vehicle 
equipment designers, suppliers, manufacturers, and modifiers. This 
document summarizes comments received in response to the draft 
guidance, responds to those comments, and describes changes made to the 
draft guidance in response to those comments. This document also 
announces the issuance of the final version of the Cybersecurity Best 
Practices for the Safety of Modern Vehicles guidance. While this is the 
final version of this iteration of the Best Practices, NHTSA routinely 
assesses cybersecurity risks as well as emerging best practices and 
will consider future updates as motor vehicles and their cybersecurity 
evolve.

DATES: The changes made in this document are effective upon 
publication.

FOR FURTHER INFORMATION CONTACT: For technical issues, please contact 
Mr. John I. Martin of NHTSA's Office of Vehicle Safety Research at 937-
366-3246 or [email protected]. For legal issues, contact Ms. Sara R. 
Bennett of NHTSA's Office of Chief Counsel at 202-366-2992 or 
[email protected].

SUPPLEMENTARY INFORMATION: This final version of the Cybersecurity Best 
Practices for the Safety of Modern Vehicles does not have the force and 
effect of law and is not a regulation. This guidance document will not 
be published in the Code of Federal Regulations but will be posted on 
NHTSA's website, www.nhtsa.gov.

I. Introduction

    In January 2021, NHTSA released its draft Cybersecurity Best 
Practices for the Safety of Modern Vehicles guidance document (``Draft 
Best Practices'' or ``guidance'') with the goal of supporting industry-
led efforts to improve the industry's cybersecurity posture and provide 
the Agency's views on how the automotive industry can develop and apply 
sound, risk-based cybersecurity management processes during the 
vehicle's entire lifecycle. As background, the Draft Best Practices 
document is an update to NHTSA's first cybersecurity best practices 
document, Cybersecurity Best Practices for Modern Vehicles (``2016 Best 
Practices''). NHTSA requested comment on the Draft Best Practices in an 
accompanying Federal Register notice.\1\
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    \1\ 86 FR 2481 (Jan. 12, 2021).
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    The Draft Best Practices builds upon agency research and industry 
progress since 2016, including emerging voluntary industry standards, 
such as the International Organization for Standardization (ISO)/SAE 
International (SAE) Draft International Standard (DIS) 21434, ``Road 
Vehicles--Cybersecurity Engineering.'' \2\ In addition, the Draft Best 
Practices references a series of industry best practice documents 
developed by the Automotive Information Sharing and Analysis Center 
(Auto-ISAC) through its members. The Draft Best Practices also reflects 
findings from NHTSA's continued research in motor vehicle 
cybersecurity, including over-the-air updates, formal verification, 
static code analysis, new learnings obtained through researchers and 
stakeholder engagement as well as continued building of our capability 
in cybersecurity testing and diagnostics. The updates included in the 
Draft Best Practices incorporate insights gained from public comments 
received in response to the 2016 guidance and from information obtained 
during the annual SAE/NHTSA Vehicle Cybersecurity Workshops.
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    \2\ ISO/SAE 21434:2021 Road Vehicles--Cybersecurity Engineering, 
available at: https://www.iso.org/standard/70918.html.
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    The Draft Best Practices touches on a wide array of issues 
associated with safety-related cybersecurity practices, and provides 
recommendations to industry on the following topics:

 General Cybersecurity Best Practices
 Education
 Aftermarket/User-Owned Devices
 Serviceability
 Technical Vehicle Cybersecurity Best Practices

    The first topic in the list, ``General Cybersecurity Best 
Practices,'' is the largest topic and discusses cybersecurity practices 
with respect to industry stakeholders. There are a variety of practices 
in this category. For example, one practice suggests that manufacturers 
should evaluate all commercial off-the-shelf and open-source software 
components used in vehicle Electronic Control Units (ECUs) against 
known vulnerabilities.\3\
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    \3\ G.12 in NHTSA's Cybersecurity Best Practices for the Safety 
of Modern Vehicles.
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    The second topic, ``Education,'' discusses the role and 
responsibilities of industry and academia in supporting an educated 
cybersecurity workforce.
    The third topic, ``Aftermarket/User-Owned Devices,'' discusses the 
issues associated with connecting aftermarket devices to vehicle 
systems. For instance, the guidance suggests that any connection to a 
third-party device should be authenticated and provided with 
appropriate, limited access.\4\
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    \4\ G.42 in NHTSA's Cybersecurity Best Practices for the Safety 
of Modern Vehicles.
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    The fourth topic, ``Serviceability,'' touches on industry's 
obligation to simultaneously provide for both cybersecurity and third-
party serviceability.
    The last topic, ``Technical Vehicle Cybersecurity Best Practices,'' 
discusses cybersecurity practices with respect to the vehicle. As an 
example, one of the 25 technical vehicle cybersecurity best practices 
suggests that network segmentation and isolation techniques should be 
used to limit connections between wireless-connected ECUs and low-level 
vehicle control systems, particularly those controlling safety critical 
functions, such as braking, steering, propulsion, and power management.
    This notice summarizes the comments received, NHTSA's responses to 
those comments, and finalizes the Draft Best Practices document. The 
final Best Practices document continues to use the numbering scheme 
introduced in the Draft Best Practices document. For example, it uses 
[G.1] through [G.45] for general cybersecurity best practices and [T.1] 
through [T.25] for technical vehicle cybersecurity best practices. 
Additions to the Draft Best Practices mean that there are some 
numbering differences between the draft and final versions of the Best 
Practices. This Federal Register notice exclusively refers to the final 
Best Practices

[[Page 55460]]

numbering scheme, rather than the draft version. Cases where there are 
differences between the draft and final numbering scheme are noted with 
a footnote. Finally, the agency stresses that the final Best Practices 
remain voluntary and non-binding, as has been the case with this 
guidance beginning with its initial 2016 edition.

II. Summary of Differences Between the Draft and Final Cybersecurity 
Best Practices for the Safety of Modern Vehicles

    The purpose of this section is to provide a summary of the 
differences between the draft and final Cybersecurity Best Practices 
for the Safety of Modern Vehicles. The next section of this document, 
``Summary of Public Comments Received in Response to Draft 
Cybersecurity Best Practices,'' will discuss the comments received and 
the reasons why these changes were made.
    The following provides a high-level summary of changes made in the 
final version. First, in response to a comment, NHTSA clarified, with a 
minor edit, that the scope of the Best Practices includes all 
individuals and organizations involved in the maintenance of a motor 
vehicle. Second, the Agency updated all references to the ISO/SAE 21434 
standard to reflect the finalized version of the subject industry 
standard, which occurred after the Draft Best Practices were published 
for comments. Third, in the General Cybersecurity Best Practices 
section, several headings were retitled in response to comments, and 
the new changes clarified terms, and altered the order of mention of 
the Auto-ISAC and standards development organizations (SDO) in some 
places to avoid unintended potential referencing to Auto-ISAC as an 
SDO. Additionally, NHTSA added a new general cybersecurity best 
practice to address future risks and bifurcated an existing one into 
two separate practices based on well-supported comments. Fourth, in the 
Technical Cybersecurity Best Practices section, NHTSA added mention of 
current cryptographic techniques and their implementation and made 
wording changes to clarify protections from unauthorized disclosure and 
accessibility to other vehicles. The Agency also added a new technical 
practice to limit firmware version rollback attacks and rewrote a 
technical practice [T.11].\5\ The new practice now reads ``[T.11] \6\ 
Employ best practices for communication of critical information over 
shared and possibly insecure channels. Limit the possibility of replay, 
integrity compromise, and spoofing. Physical and logical access should 
also be highly restricted.'' Fifth, NHTSA added definitions of ``global 
symmetric keys'' and ``recovery'' to the appendix's Terms and 
Descriptions section. Finally, NHTSA updated and added minor wording 
changes and references throughout, including addressing clerical 
errors.
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    \5\ In the draft version, this was T.10.
    \6\ In the draft version, this was T.10.
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III. Summary of Public Comments Received in Response to Draft 
Cybersecurity Best Practices

    NHTSA received comments from a total of 38 entities in response to 
the Draft Best Practices, published in January 2021. These comments 
came from government entities,\7\ industry associations,\8\ standards 
development organizations,\9\ automotive and equipment 
manufacturers,\10\ consumer and safety advocacy organizations,\11\ 
university and research organizations,\12\ and individuals.\13\ The 
comments represent an evolution of vehicle cybersecurity opinion among 
stakeholders and the general public. Comments to the 2016 guidance 
tended to be general and higher-level (i.e., bigger-picture). In 
contrast, comments received in response to the Draft Best Practices 
focused on discrete issues important to commenters. This evolution is 
also likely due to the introduction of vehicle-specific cybersecurity 
standards and best practices in the automotive sector. Overall, most 
commenters seemed supportive of NHTSA's efforts to encourage continual 
progress in the automotive sector through the issuance of best 
practices, though there was some divergence as to the details of what 
those best practices should contain, the level of detail necessary to 
fulfill the agency's goals, and other specific topics commenters stated 
NHTSA should address. The aggregated comments presented several high-
level themes, and thus, this document presents comments organized by 
the following categories of request:
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    \7\ California Highway Patrol.
    \8\ Alliance for Automotive Innovation, American Alliance for 
Vehicle Owner's Rights, American Trucking Association, Auto Care 
Association, Automotive Aftermarket Suppliers Association, 
Automotive Recyclers Association, Specialty Equipment Market 
Association, National Motor Freight Traffic Association, National 
Automobile Dealers Association, Motor Equipment Manufacturers 
Association and Consumer Technology Association.
    \9\ SAE and Institute of Electrical and Electronics Engineers.
    \10\ General Motors LLC, Toyota Motor Corporation, Continental 
Automotive Systems, Denso Corporation, ZF North America, Robert 
Bosch GmbH, Amazon Web Services, Blackberry Corporation, AT&T, 
GeoTab, Nuro, Arilou Automotive Cybersecurity and LKQ Corporation.
    \11\ Center for Auto Safety, Privacy4Cars, SecuRepairs and 
Digital Right to Repair Coalition.
    \12\ Carnegie Mellon Software Engineering Institute, Sandia 
National Laboratories, Underwriters Laboratories LLC.
    \13\ Norman Field, Rik Farrow,Ryan Moss and Howard Hoffman.
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     More specifics in the guidance;
     Industry collaboration;
     Minor editorial amendments;
     Additional references to ISO/SAE 21434;
     Additional references to other standards;
     Clarification of entity designations;
     Changes in scope; and
     Right to repair.
    In the sections that follow, NHTSA summarizes each category of 
major comments received in response to the Draft Best Practices and the 
agency's response.

a. Commenter Requested More Specifics in the Guidance

    Several commenters requested that NHTSA make certain language in 
the guidance more specific to address issues important to the 
commenter. As background, NHTSA intends to maintain wide applicability 
in the Draft Best Practices, so that it can encompass the many industry 
stakeholders, variety of business models, and vehicle and equipment 
architectures available on the market. This guidance is also intended 
to be flexible enough to encompass future business models and vehicle 
and equipment designs, to help ensure that this guidance remains 
helpful and relevant beyond a single point in time. Even so, NHTSA 
found it possible to integrate several suggestions from commenters in 
response to requests for more specificity. As such, NHTSA added two 
definitions to the document's glossary, and made the changes described 
below.
    The two definitions that NHTSA added in response to comments are 
for the terms, ``recovery,'' and ``global symmetric keys.'' The 
Institute of Electrical and Electronics Engineers (IEEE), a standards 
setting professional organization, suggested defining the term 
``recovery'' in the context of referencing the National Institute of 
Standards and Technology (NIST) Cybersecurity Framework's five 
principal functions ``Identify, Protect, Detect, Respond and Recover.'' 
IEEE suggested that the document did not describe what was meant by 
``recovery.'' Toyota Motor Corporation (Toyota) and Geotab suggested 
defining the specific term ``global symmetric keys'' because, in their 
opinion, the meaning may not

[[Page 55461]]

be obvious. NHTSA considered the merits of adding these new definitions 
for improving clarity and agreed that their addition would be 
beneficial for public understanding, and thus, added them to the final 
Best Practice's appendix in ``Terms and Definitions''.
    In section 8.2 of the Draft Best Practices, ``Cryptographic 
Credentials,'' Sandia National Laboratories (Sandia) and DENSO 
Corporation (Denso) suggested additional specific discussion of 
cryptographic techniques and standards. In response, NHTSA has modified 
section 8.2 with additional text and a slight title change that 
reflects section 8.2's new focus on techniques.
    Sandia also expressed the comment that, ``The claim that Public key 
cryptography techniques are more secure than symmetric key systems 
should be caveated with `properly implemented techniques' are 
`generally' more secure. . . .''.\14\ While Sandia made this comment 
with respect to section 8.3 of the Draft Best Practices, ``Vehicle 
Diagnostic Functionality,'' NHTSA responded to Sandia's comment by 
incorporating the text ``While the selection of appropriate 
cryptographic techniques is an important design criterion, it should be 
noted that implementation issues often determine any system's 
security'' into section 8.2. NHTSA considered Sandia's assertion to be 
correct, and NHTSA agrees that implementation issues are very 
important.
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    \14\ See Comment ID ``NHTSA-2020-0087-0009'' for Document 
``NHTSA-2020-0087-0002'' on the regulations.gov website.
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    NHTSA also incorporated a comment from SAE that asked for technical 
guidance that would limit firmware version rollback attacks where an 
attacker may use software update mechanisms to place older, more 
vulnerable software on a targeted device. NHTSA agrees that the 
practice of manufacturers allowing the installation of older, 
potentially vulnerable versions of firmware in vehicles and vehicle 
equipment should be avoided whenever possible. In response, NHTSA added 
practice [T.23].
    Because of NHTSA's desire for the document to remain broadly 
applicable, many comments asking for additional specifics were not 
incorporated into the guidance. For instance, NHTSA did not accept 
comments suggesting that the agency explicitly define terms such as 
``lifecycle,'' ``end-of-life,'' and ``state of the art,'' among others. 
NHTSA acknowledges that many of these terms may have different meanings 
to different companies and stakeholders, but NHTSA did not believe it 
would be appropriate to define these terms in such a way that might 
inadvertently suggest limitations to or conflicts with company 
responsibilities, such as manufacturers' responsibility to notify NHTSA 
of any safety defect in its motor vehicles or motor vehicle 
equipment.\15\
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    \15\ 49 U.S.C. 30118(c).
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    Similarly, while NHTSA encourages companies to pay close attention 
to cybersecurity throughout its corporate structures and supply chain, 
NHTSA does not view this guidance as a mechanism to suggest how 
corporate responsibilities among companies should be distributed. This 
guidance does not attempt to provide any particular view of the 
automotive supply chain, and NHTSA recognizes that many of these 
considerations may be handled via contract. Although ISO/SAE 21434 does 
address supply chain responsibilities to some extent, NHTSA's Best 
Practices purposefully does not provide such details.
    In other cases of requested specificity, NHTSA determined that some 
commenters' requests inadvertently resulted in limiting the 
applicability of the document. As stated before, one of NHTSA's 
underlying goals of this document was to ensure it remains accessible 
to a wide audience and all of NHTSA's regulated entities.
    NHTSA also tries to maintain the document's generality by limiting 
language specific to a particular corporate process, perhaps even 
specific to a particular corporation. Comments that make suggestions 
encompassing specific corporate processes have not been incorporated 
into the updated document.
    In addition, a comment asked NHTSA to address forensic data 
retrieval. NHTSA recognizes the importance of forensic data retrieval 
but has determined that the subject is out-of-scope for this document.

b. Commenter Encourages Industry Collaboration

    Many commenters expressed the sentiment that industry collaborative 
efforts are a good idea, including the Alliance for Automotive 
Innovation (Alliance) and Amazon Web Services (Amazon), both of which 
provided specific comments encouraging collaboration. The Alliance 
suggested that NHTSA create a new section on emerging risks where there 
may not be established best practices developed to manage those risks. 
The Alliance suggested that this new section should include high-level 
recommendations to encourage industry-wide collaboration to establish 
best practices to treat those risks. Amazon suggested NHTSA should 
encourage industry collaboration to identify attempted and successful 
exploitations and attacks not previously considered in the design and 
assessment phases.
    NHTSA agrees with the importance of industry collaboration, 
especially within the automotive cybersecurity realm. Therefore, NHTSA 
has encouraged membership and active participation in the Auto-ISAC and 
collaboration through its annual cybersecurity forum that the agency 
holds with SAE. In response to these commenters, NHTSA added a new 
general practice [G.24] that states: ``As future risks emerge; industry 
should collaborate to expediently develop mitigation measures and best 
practices to address new risks.'' NHTSA believes that this addition and 
the rest of the guidance covers both commenters' suggestions.

c. Commenter Requested Minor Editorial Amendments

    Many commenters provided a wealth of suggested additional word 
choices, terminology changes, and phrasing modifications. NHTSA 
appreciates these suggestions and adopted these changes wherever 
possible and is grateful for the improvements these suggestions 
provide.
    Multiple comments \16\ pointed out a typographical error in section 
4.5 where ``[G.27[a]-[c]]'' \17\ should have been ``[G.28[a]-[c].'' 
\18\ NHTSA adopted the suggested change. Other editorial amendments 
include modifying the word ``standards'' in [G.9] to ``expectations.'' 
In the draft Best Practices, [G.9] stated ``Clear cybersecurity 
standards should be specified and communicated to the suppliers that 
support the intended protections.'' NHTSA adopted the change to the 
word ``expectations'' because commenters suggested they needed 
additional clarification as to what word ``standards'' means in that 
particular practice. NHTSA believes ``expectations'' would maintain the 
agency's intended breadth while also clarifying any ambiguity for 
stakeholders.
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    \16\ ZF North America, Arilou Automotive Cybersecurity, National 
Motor Freight Traffic Administration.
    \17\ In the draft version, this was G.26.
    \18\ In the draft version, this was G.27.
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    Another commenter suggested that NHTSA remove ``that'' from ``NHTSA 
recommends that:'' in section 4.3 of the Draft Best Practices. NHTSA 
adopted this edit accordingly.
    Some commenters suggested changes to section titles to add 
additional clarity

[[Page 55462]]

for stakeholders. In two instances, NHTSA adopted those suggestions to 
change section titles. Section 4.2.7 was originally titled 
``Penetration Testing and Documentation'' in the draft guidance and is 
now titled ``Cybersecurity Testing and Vulnerability Identification'' 
in the final guidance. NHTSA felt that the new title was appropriately 
general. Similarly, section 4.2.4 was originally titled ``Unnecessary 
Risk Removal'' and is now ``Removal or Mitigation of Safety-Critical 
Risks.'' The new title better describes the section.
    SAE suggested changes to [T.4] \19\ that changed the existing text 
to ``Cryptographic credentials that provide an authorized, elevated 
level of access to vehicle computing platforms should be protected from 
unauthorized disclosure or modification''. NHTSA welcomes this change 
because it additionally emphasizes the consequences of modifying 
platform credentials.
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    \19\ In the draft version, this was T.3.
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    Several commenters recommended minor amendments to [T.5] \20\ ``Any 
credential obtained from a single vehicle's computing platform should 
not provide access to multiple vehicles.'' The technical guidance now 
reads ``other vehicles'' rather than ``multiple vehicles'' as was 
included in the draft guidance. NHTSA feels that the use of the word 
``other'' more clearly focuses the issues involved in using universally 
applicable credentials.
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    \20\ In the draft version, this was T.4.
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    National Motor Freight Traffic Association (NMFTA) recommended 
minor amendments to general practice [G.6] ``Manufacturers should 
consider the risks associated with sensor vulnerabilities and potential 
sensor signal manipulation efforts such as GPS spoofing, road sign 
modification, Lidar/Radar jamming and spoofing, camera blinding, or 
excitation of machine learning false positives.'' The general guidance 
now reads ``. . . camera blinding, and excitation . . .'' rather than 
``. . . camera blinding, or excitation. . . .'' NHTSA agrees with 
NMFTA's comment that the use of ``or'' rather than ``and'' incorrectly 
suggests that manufacturers could focus on any one of the presented 
spoofing issues rather than considering all the spoofing issues.
    SAE suggested that [G.10] needed to focus on hardware and software 
rather than just software. In the Draft Best Practices, general 
practice [G.10] stated ``Manufacturers should maintain a database of 
operational software components used in each automotive ECU, each 
assembled vehicle, and a history log of version updates applied over 
the vehicle's lifetime.'' NHTSA agrees that software inventory 
management alone is not sufficient and made changes to [G.10] to 
include a discussion of inventory management of both hardware and 
software. Robert Bosch GmbH (Bosch) additionally suggested that the 
subject of [G.10] needed to be ``Suppliers and vehicle manufacturers'' 
rather than ``Manufacturers.'' NHTSA agrees with the change because it 
maintains the desired generality while directing the reader to specific 
entities.
    In the Draft Best Practices, general practice [G.30] \21\ stated 
``Organizations should document the details of each identified and 
reported vulnerability, exploit, or incident applicable to their 
products. These documents should include information from onset to 
disposition with sufficient granularity to support response 
assessment.'' Underwriters Laboratories (UL) suggested rephrasing the 
second sentence as: ``The nature of the vulnerability and the rationale 
for how the vulnerability is managed should also be documented.'' NHTSA 
agrees that UL's suggested wording is an improvement. NHTSA also felt 
that [G.30] \22\ could be better expressed as two separate general 
practices and made a new general practice to reflect UL's wording.
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    \21\ In the draft version, this was G.29.
    \22\ In the draft version, this was G.29.
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    SAE suggested changes to [G.41] \23\ in the Draft Best Practices, 
which stated ``The automotive industry should consider the incremental 
risks that could be presented by these devices when connected with 
vehicle systems and provide reasonable protections.'' The commenter 
suggested removing the word ``incremental,'' changing ``automotive 
industry'' to ``automotive manufacturers,'' and changing ``these 
devices'' to ``user owned or aftermarket devices.'' NHTSA declines to 
change ``automotive industry'' to ``automotive manufacturers'' because 
the goal of this guidance document is to retain broad utility for the 
entire automotive industry, not just manufacturers. NHTSA agreed to 
remove the word ``incremental'' from the general practice and to 
replace the term ``these devices'' with a more accurate phrase, ``user 
owned or aftermarket devices.''
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    \23\ In the draft version, this was G.39.
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    In the Draft Best Practices, [T.11] \24\ stated ``Critical safety 
messages, particularly those passed across non-segmented communication 
buses, should employ a message authentication method to limit the 
possibility of message spoofing.'' SAE felt that [T.11] \25\ needed to 
be reworded as: ``Employ best practices for communication of critical 
information over shared and possibly insecure channels. Limit the 
possibility of replay, integrity compromise, and spoofing. Physical and 
logical access should also be highly restricted.'' NHTSA adopted SAE's 
suggested language for technical practice because the new wording 
expresses more general guidance than the draft version while 
encompassing the draft version's meaning.
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    \24\ In the draft version, this was T.10.
    \25\ In the draft version, this was T.10.
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    There were many other suggestions for minor wording or phrasing 
changes that NHTSA considered. NHTSA adopted those that would not 
change the underlying intent of that particular section of the guidance 
document, but many suggestions from commenters would have worked to 
either limit or narrow the scope of the guidance. As such, those 
suggestions were not adopted since they would be contrary to the intent 
and goals of this document.

d. Commenter Requested Additional References to ISO/SAE 21434

    ISO/SAE 21434 is a newly developed standard titled ``Road 
Vehicles--Cybersecurity Engineering.'' \26\ This standard serves as an 
overarching industry consensus standard for vehicle cybersecurity, and 
it is extensively referenced in NHTSA's ``Cybersecurity Best Practices 
for the Safety of Modern Vehicles.'' Many commenters pointed out that 
NHTSA referenced the earlier Draft International Standard (DIS) version 
of ISO/SAE 21434, and suggested that NHTSA needed to update the 
references in the final Best Practices to the final ISO/SAE 21434 
version, which was due to be released in Fall 2021. NHTSA followed this 
advice. In the final Best Practices, NHTSA has changed the latest the 
guidance to reflect the content of the latest ``FDIS'' or ``Final Draft 
International Standard'' version of ISO/SAE 21434.
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    \26\ ISO/SAE 21434:2021 Road vehicles--Cybersecurity 
engineering, available at: https://www.iso.org/standard/70918.html 
and https://www.saemobilius.sae.org.
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    While NHTSA extensively referenced ISO/SAE 21434, the commenters 
pointed out areas where NHTSA could have included a reference to a 
relevant section of ISO/SAE 21434 and did not. As an example, 
commenters pointed out that [G.12] and [G.37] \27\ could refer to the 
relevant clauses of ISO/SAE 21434. NHTSA adopted these suggestions and 
added a reference to ISO/SAE 21434

[[Page 55463]]

clause 6 in [G.12]. General practice [G.37] \28\ now references 
requirements in clauses 5 and 6 of ISO/SAE 21434. Another commenter 
corrected NHTSA's reference to ISO/SAE 21434 in a footnote to general 
practice [G.16]. NHTSA accepted that correction.
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    \27\ In the draft version, this was G.35.
    \28\ In the draft version, this was G.35.
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    NHTSA also included the website https://www.saemobilius.sae.org as 
a source for ISO/SAE 21434 in addition to the previously referenced 
https://www.iso.org.

e. Commenter Requested Additional References to Other Standards

    Another category of comments requested that NHTSA provide new 
references to additional source material that were favored by the 
commenter. In many cases, NHTSA was able to incorporate these 
suggestions. NHTSA added only those references and referenced materials 
that the agency found were: (1) Sufficiently high level; (2) Specific 
to automotive industry or could be obviously applied to the automotive 
industry; (3) Not under development; and/or (4) Not duplicative of 
information or references already included in the Draft Best Practices.
    For example, one commenter stated that NHTSA should add references 
to the NIST cryptography standards to supplement technical practice 
[T.4],\29\ dealing with cryptographic credentials. NHTSA decided that 
this modification met the criteria described above, and the agency 
adopted this suggestion by adding a technical practice [T.3] and a 
reference to NIST's Federal Information Processing Standards (FIPS) 140 
Series. The FIPS 140 series is a set of documents updated by NIST that 
describes minimum standards for cryptography.
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    \29\ In the draft version, this was T.3.
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    Another commenter stated that NHTSA should reference ISO 24089 
``Road vehicles--Software update engineering'' in the Best Practices. 
NHTSA did not incorporate this comment because ISO 24089 is under 
development at this time. NHTSA may revisit this decision in future 
iterations of its cybersecurity best practices after ISO 24089 is 
finalized.
    NMFTA requested that NHTSA reference the Cybersecurity and 
Infrastructure Security Agency's (CISA's) binding operational directive 
20-01 in general practice [G.27]'s \30\ discussion of vulnerability 
reporting. NHTSA agreed with this change and felt that it provided 
support for the guidance.
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    \30\ In the draft version, this was G.26.
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    In response to a comment from SAE, NHTSA also added a reference to 
a NIST white paper titled ``Mitigating the Risk of Software 
Vulnerabilities by Adopting a Secure Software Development Framework 
(SSDF)'' for general practice [G.22], dealing with best practices for 
secure software development.
    Responding to a comment from NMFTA, NHTSA added a footnote 
reference to the SAE CyberAuto Challenge and the Cyber Truck Challenge 
as examples for general practice [G.40],\31\ dealing with educational 
efforts targeted at workforce development in the field of automotive 
cybersecurity. NHTSA also used this additional footnote to call out 
NHTSA's efforts to fund and develop cybersecurity curricula.
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    \31\ In the draft version, this was G.38.
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    Other commenters requested that NHTSA add in references to the 
World Forum for Harmonization of Vehicle Regulation's (WP.29) United 
Nations (UN) Regulation 155--``Cyber security and cyber security 
management system.'' In most cases, the public comments recommended 
high-level alignment, without further specifying the sources of 
potential misalignment that may have been a concern. UN ECE 155 is a 
type-approval regulation \32\ that establishes not only recommended 
practices but also sufficiency standards for approval. Standards for 
type approval are well beyond the scope and intent of NHTSA's Best 
Practices document. Therefore, NHTSA did not explicitly reference the 
UN ECE 155. NHTSA could revisit this topic in future iterations based 
on more specific public feedback.
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    \32\ UN ECE 155 is a regulation established under the United 
Nations Economic Commission for Europe (UNECE) 1958 Agreement 
concerning the Adoption of Uniform Technical Prescriptions for 
Wheeled Vehicles, Equipment and Parts which can be Fitted and/or be 
Used on Wheeled Vehicles and the Conditions for Reciprocal 
Recognition of Approvals Granted on the Basis of these Prescriptions 
(Available at https://unece.org/trans/main/wp29/wp29regs), and the 
United States is not party to this agreement. Further, UN Regulation 
155 is a regulation for type approving authorities, and the United 
States is not a country that engages in type approval of motor 
vehicles or motor vehicle equipment.
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f. Commenter Requested Clarification of Entity Designations

    Several comments pointed out that the NHTSA's Cybersecurity Best 
Practices seemed to falsely suggest that the Auto-ISAC is a standard 
setting organization (SSO). NHTSA has modified general practices [G.18] 
and [G.23] in an effort to correct this impression. Even so, these 
modifications should not be interpretated as anything more than textual 
clarifications. The modifications do not represent any change in 
NHTSA's position that guidance to industry, whether from a SSO or not, 
can be valuable to encourage progress in cybersecurity practices of the 
automotive industry.

g. Commenters Requested Changes in Scope

    Many commenters requested a variety of changes in scope for the 
Draft Best Practices. Commenters diverged in their requests for changes 
to the scope. NHTSA did not incorporate most of the requested scope 
changes because NHTSA carefully considered the scope of the Draft Best 
Practices document at the development and drafting stages, and NHTSA 
believes that the existing scope of the document is most compatible 
with its mission and goals for this document. For example, narrowing 
the scope might imply inaccurately that NHTSA does not intend this 
guidance to be useful to all its regulated entities, and broadening the 
scope might exceed the agency's intended audience.
    While most comments concerning the document's scope were not 
incorporated, NHTSA responded to the National Automobile Dealers 
Association's comments concerning the critical role of automotive 
dealers by adding the word ``maintenance'' to the following text of the 
Scope, which was an explicit clarification that scope includes that 
function: ``Importantly, all individuals and organizations involved in 
the design, manufacturing, assembly and maintenance of a motor vehicle 
have a critical role to play with respect to vehicle cybersecurity.''
    Many commenters felt that NHTSA needed to address heavy trucks more 
explicitly and directly, but NHTSA believes this would be unnecessary 
since the scope of the Draft Best Practices already includes heavy 
trucks.
    Other commenters felt that NHTSA needed to more explicitly address 
vehicles equipped with Automated Driving Systems (ADS), asserting that 
these vehicles would have cybersecurity needs much different from 
modern vehicles. NHTSA believes that the underlying technical sources 
of cybersecurity vulnerabilities as well as risk-based approaches and 
toolsets to address them are unlikely to be substantially different for 
vehicles equipped with ADS. Therefore, at the levels of guidance 
included, the Draft Best Practices already covers vehicles equipped 
with ADS, and NHTSA believes that any more specificity for ADS is 
unnecessary at this time.

[[Page 55464]]

However, the Agency believes that the societal risk tolerance 
associated with cybersecurity risks for vehicles equipped with ADS may 
be significantly lower than for traditional vehicles, and, thus, the 
Agency will continue to monitor factors around these recommendations 
with incoming research results and consider them in future updates.
    Some commenters stated that NHTSA should explicitly address 
enterprise information technology (IT) issues. While NHTSA agrees that 
enterprise IT security is an important topic, NHTSA specifically 
avoided making suggestions regarding internet infrastructure that do 
not directly touch vehicles. NHTSA recognizes that a hypothetical 
situation, such as the theft of vehicle code signing keys from a poorly 
secured, internet-connected server, could be an example of an 
enterprise IT security issue that could impact a vehicle. However, as 
part of this document's scope, NHTSA focuses primarily on those 
cybersecurity issues that directly impact vehicles, and thus occupant 
and road user, safety. In addition to cybersecurity safety issues, 
NHTSA is invested in vehicle theft prevention and engages in activities 
to reduce motor vehicle theft through its Vehicle Theft Prevention 
Program.
    Another set of commenters requested that NHTSA expand the scope of 
the Draft Best Practices to address a variety of consumer privacy 
issues. Many of these commenters indicated that they believed that a 
substantial part of cybersecurity implicates privacy and privacy cannot 
be separated from cybersecurity. In this vein, some comments suggested 
that NHTSA needed to address a concept called the confidentiality, 
integrity, and availability triad, aka ``CIA triad.'' \33\ While NHTSA 
agrees about the general importance of the topic of consumer 
confidentiality, NHTSA's Best Practices retains its intended focus on 
cybersecurity, particularly those cybersecurity issues that could 
impact the safety of the vehicle or equipment safety. NHTSA believes 
this focus most closely aligns with its safety mission. We believe 
privacy issues can and should be addressed elsewhere.
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    \33\ https://en.wikipedia.org/wiki/Information_security.
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    Finally, many commenters expressed concern that NHTSA's 
Cybersecurity Best Practices focused on the automotive industry at the 
expense of advising the consumer. NHTSA's intended audience for the 
Best Practices is the regulated industry. The primary responsibility 
for vehicle and equipment safety, including that of vehicle software 
and any cybersecurity protections applied, is industry, and NHTSA 
retains this focus in the final version. NHTSA is interested in 
consumer education topics, but the agency believes that an educated 
consumer provides an additional layer of protection that does not 
change the best practices recommendations to the automotive industry.

h. Right To Repair

    Many comments discussed right-to-repair issues. Some of the right-
to-repair comments suggested that NHTSA assign software rights to 
various parties. As stated in the Draft Best Practices and 
elsewhere,\34\ NHTSA considers serviceability to be so important that 
in the Best Practices retain a separate section on the issue that 
includes the general practice [G.45]: \35\ ``The automotive industry 
should provide strong vehicle cybersecurity protections that do not 
unduly restrict access by alternative third-party repair services 
authorized by the vehicle owner.'' Providing any party with a 
particular access or right to vehicle software is outside the scope and 
intent of this document, even though NHTSA's interest in facilitating 
serviceability without undue restrictions remains the same. The Best 
Practices do not hinder industry's ability to facilitate appropriate 
levels of access to any party while achieving cybersecurity goals.
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    \34\ https://www.nhtsa.gov/sites/nhtsa.gov/files/documents/nhtsa_testimony_in_response_to_ma_committee_letter_july_20_2020.pdf.
    \35\ In the draft version, this was G.43.
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IV. Economic Analysis for Cybersecurity Best Practices for the Safety 
of Modern Vehicles

    NHTSA is finalizing its Cybersecurity Best Practices for the Safety 
of Modern Vehicles, which is non-binding (i.e., voluntary) guidance 
provided to serve as a resource for industry on safety-related 
cybersecurity issues for motor vehicles and motor vehicle equipment. As 
guidance, the document touches on a wide array of issues related to 
safety-related cybersecurity practices, and provides recommendations to 
industry on the following topics: (1) General Cybersecurity Best 
Practices, (2) Education, (3) Aftermarket/User Owned Devices, (4) 
Serviceability, and (5) Technical Vehicle Cybersecurity Best Practices.
    NHTSA considered the potential benefits and costs that may occur if 
companies in the automotive industry decide to integrate the 
recommendations in the Best Practices into their business practices. 
The following is a summary of the considerations that NHTSA evaluated 
for purposes of this section.
    First, although as guidance the Best Practices is voluntary, NHTSA 
expects that many entities will conform their practices to the 
recommendations endorsed by NHTSA. NHTSA believes that the 
Cybersecurity Best Practices for the Safety of Modern Vehicles serve as 
means of facilitating common understanding across industry regarding 
best practices for cybersecurity.
    Second, the diversity among the entities to which the Best 
Practices apply is vast. The recommendations found in Cybersecurity 
Best Practices for the Safety of Modern Vehicles are necessarily 
general and flexible enough to be applied to any industry entity, 
regardless of size or staffing. The recommendations contained within 
the best practices are intended to be applicable to all individuals and 
organizations involved in the design, development, manufacture, and 
assembly of a motor vehicle and its electronic systems and software. 
These entities include, but are not limited to, small and large volume 
motor vehicle and motor vehicle equipment designers, suppliers, 
manufacturers, modifiers, and alterers. NHTSA recognizes that there is 
a great deal of organizational diversity among the intended audience, 
resulting in a variety of approaches, organizational sizes, and 
staffing needs. NHTSA also expects that these entities have varying 
levels of organizational maturity related to cybersecurity, and varying 
levels of potential cybersecurity risks. These expectations, combined 
with NHTSA's lack of detailed knowledge of the organizational maturity 
and implementation of any recommendations contained within the 
guidance, make it difficult for NHTSA to develop a reasonable 
quantification of the per-organization cost of implementing the 
recommendations.
    Third, any costs associated with applying the Best Practices would 
be limited to the incremental cost of applying the new recommendations 
included in the document (as opposed to those in the 2016 Best 
Practices). The updated Cybersecurity Best Practices for the Safety of 
Modern Vehicles document highlights a total of 70 enumerated best 
practices, 21 of which could be considered ``new'' relative to the 
first version published in 2016.
    Fourth, costs could be limited by organizations who have 
implemented some of the recommendations prior to this request for 
comment. NHTSA is unaware of the extent to which various entities have 
already implemented NHTSA's recommendations, and

[[Page 55465]]

determining the incremental costs associated with full implementation 
of the recommendations is effectively impossible without detailed 
insight into the organizational processes of every company.
    Fifth, many of NHTSA's recommendations lean very heavily on 
industry standards, such as ISO/SAE 21434. Three of the 21 ``new'' best 
practices simply reference the ISO/SAE 21434 industry standard. Since 
many aspects of NHTSA's recommendations are mapped to an industry 
standard, costs would also be limited for those companies who are 
adopting ISO/SAE 21434 already. Thus, it would be very difficult to 
parse whether a company implemented ISO/SAE 21434 or whether it had 
decided to adopt NHTSA's voluntary recommendations. While the Best 
Practices have some recommendations \36\ that cannot be mapped to an 
industry standards document at this time, most of those recommendations 
involve common vehicle engineering and sound business management 
practices, such as risk assessment and supply-chain management. For 
these recommendations, NHTSA's inclusion in the Best Practices serve as 
a reminder.
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    \36\ For example, G.6 in Section 4.2.3 recommends consideration 
of sensor vulnerabilities as part of risk assessment; and G.10 and 
G.11 in Section 4.2.6 recommend tracking software components on 
vehicles in a manner similar to hardware components.
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    Regarding benefits, entities that do not implement appropriate 
cybersecurity measures, like those guided by these recommendations, or 
other sound controls, face a higher risk of cyberattack or increased 
exposure in the event of a cyberattack, potentially leading to safety 
concerns for the public. Implementation of the best practices can, 
therefore, facilitate ``cost prevention'' in the sense that failure to 
adopt appropriate cybersecurity practices could result in other direct 
or indirect costs to companies (i.e., personal injury, vehicle damage, 
warranty, recall, or voluntary repair/updates).
    The best practices outlined in this document help organizations 
measure their residual risks better, particularly the safety risks 
associated with potential cybersecurity issues in motor vehicles and 
motor vehicle equipment that they design and manufacture. Further, the 
document provides a toolset of techniques organizations can utilize 
commensurate to their measured risks and take appropriate actions to 
reduce or eliminate them. Doing so could lower the future liabilities 
these risks represent in terms of safety risks to public and business 
costs associated with addressing them.
    In addition, quantitatively positive externalities have been shown 
to stem from vehicle safety and security measures (Ayres & Levitt, 
1998). The high marginal cost of cybersecurity failures (crashes) 
extends to third parties. Widely accepted adoption of sound 
cybersecurity practices limits these potential costs and lessens 
incentives for attempts at market disruption (i.e., signal 
manipulation, Global Positioning System (GPS) spoofing, or reverse 
engineering).

    Issued in Washington, DC, under authority delegated in 49 CFR 
1.95 and 501.8.
Cem Hatipoglu,
Associate Administrator, Vehicle Safety Research.
[FR Doc. 2022-19507 Filed 9-8-22; 8:45 am]
BILLING CODE 4910-59-P