ETSI EN 304 634 V1.0.0 (2026-07)

Draft ETSI EN 304 634 V1.0.0 (2026-07)

HARMONISED EUROPEAN STANDARD
Cyber Security (CYBER);
CRA;
Cybersecurity requirements for personal wearable

2 Draft ETSI EN 304 634 V1.0.0 (2026-07)

Reference
DEN/CYBER-EUS-003
Keywords
CRA, cybersecurity, wearable
ETSI
650 Route des Lucioles
F-06921 Sophia Antipolis Cedex - FRANCE

Tel.: +33 4 92 94 42 00  Fax: +33 4 93 65 47 16

Siret N° 348 623 562 00017 - APE 7112B
Association à but non lucratif enregistrée à la
Sous-Préfecture de Grasse (06) N° w061004871

Important notice
The present document can be downloaded from the
ETSI Search & Browse Standards application.
The present document may be made available in electronic versions and/or in print. The content of any electronic and/or
print versions of the present document shall not be modified without the prior written authorization of ETSI. In case of any
existing or perceived difference in contents between such versions and/or in print, the prevailing version of an ETSI
deliverable is the one made publicly available in PDF format on ETSI deliver repository.
Users should be aware that the present document may be revised or have its status changed,
this information is available in the Milestones listing.
If you find errors in the present document, please send your comments to
the relevant service listed under Committee Support Staff.
If you find a security vulnerability in the present document, please report it through our
Coordinated Vulnerability Disclosure (CVD) program.
Notice of disclaimer & limitation of liability
The information provided in the present deliverable is directed solely to professionals who have the appropriate degree of
experience to understand and interpret its content in accordance with generally accepted engineering or
other professional standard and applicable regulations.
No recommendation as to products and services or vendors is made or should be implied.
In no event shall ETSI be held liable for loss of profits or any other incidental or consequential damages.

Any software contained in this deliverable is provided "AS IS" with no warranties, express or implied, including but not
limited to, the warranties of merchantability, fitness for a particular purpose and non-infringement of intellectual property
rights and ETSI shall not be held liable in any event for any damages whatsoever (including, without limitation, damages
for loss of profits, business interruption, loss of information, or any other pecuniary loss) arising out of or related to the use
of or inability to use the software.
Copyright Notification
No part of this document may be reproduced in any form, by any means and in any media, without the prior written
authorization of ETSI and except as expressly permitted below.
By way of exception and when the document is a normative deliverable (European Standard (EN),
Technical Specification (TS), Group Specification (GS) or ETSI Standard (ES)), ETSI authorizes to reproduce
and incorporate into products, services and technical documentation only those extracts (e.g. templates) that are strictly
necessary for the technical implementation of the normative deliverable, to ensure compliance with the latter.
Nothing in this notice shall be construed as limiting any mandatory exceptions to copyright provided by applicable law.

© ETSI 2026.
All rights reserved.
ETSI
3 Draft ETSI EN 304 634 V1.0.0 (2026-07)
Contents
Intellectual Property Rights . 10
Foreword . 10
Modal verbs terminology . 11
Introduction . 11
1 Scope . 12
2 References . 12
2.1 Normative references . 12
2.2 Informative references . 12
3 Definition of terms, symbols and abbreviations . 13
3.1 Terms . 13
3.2 Symbols . 17
3.3 Abbreviations . 17
4 Product context . 19
4.0 Introduction . 19
4.0.1 General . 19
4.0.2 Personal wearable that have a health monitoring purpose . 20
4.0.3 Personal wearable that are intended for the use by and for children . 20
4.1 Product functions . 20
4.1.0 Introduction. 20
4.1.1 Health monitoring functionalities (essential functionalities) . 20
4.1.2 Location-based functionalities (essential functionalities) . 21
4.1.3 Parental Control (essential functionalities) . 21
4.1.4 Notification functionalities (essential functionalities) . 22
4.1.5 Input commands from user or other connected devices (supporting functionalitie s) . 22
4.1.6 Data monitoring and storage (supporting functionalities). 22
4.1.7 General functionalities (supporting functionalities) . 22
4.1.8 Summary of the personal wearable functions . 22
4.1.9 Data assets . 23
4.2 Product Architecture. 24
4.2.0 Introduction. 24
4.2.1 Personal wearable that have a health monitoring purpose architecture . 24
4.2.2 Personal wearable that are intended for the use by and for children architecture . 25
4.3 Operational Environment . 27
4.3.1 General description . 27
4.3.2 Physical operational environment . 27
4.3.3 Logical operational environment . 27
4.3.4 Connectivity aspects . 27
4.4 Distribution of Security Functions . 28
4.5 Users . 28
4.5.1 End-Users . 28
4.5.2 Manufacturers . 28
4.6 Use cases . 29
5 Technical requirements for personal wearables . 29
5.1 Introduction - Applicability of the requirements . 29
5.2 Appropriate level of cybersecurity . 29
5.2.0 Appropriate level of cybersecurity introduction . 29
5.2.1 [USERNOT-NOSECFUC] User notifications on not available security functions . 29
5.2.2 [USERNOT-SECREL] Language and representation for security-related user notifications. 29
5.2.3 [GUI-SECCONF] Visual representation of security-related configuration via GUIs . 29
5.2.4 [BACKUP-TRANS] Data transfer mechanisms for loss sensitive data . 30
5.2.5 [BACKUP-AUTOTRANS] Automatic data transfer mechanisms for loss sensitive data . 30
5.2.6 [BACKUP-EXPORT] Data export mechanisms for loss sensitive data . 30
5.3 No known exploitable vulnerabilities . 30
ETSI
4 Draft ETSI EN 304 634 V1.0.0 (2026-07)
5.3.0 No known exploitable vulnerabilities introduction . 30
5.3.1 [NKEV-MKAV] No known exploitable vulnerabilities . 30
5.3.2 [NKEV-INIT-UPD] Initial security update before or during first use . 30
5.4 Secure by default configuration . 31
5.4.0 Secure by default configuration introduction . 31
5.4.1 [SDC-AUM-FH] Default configuration of authentication for functions whose use can cause harm. 31
5.4.2 [SDC-SUM-AUTO] Default configuration of automated security updates . 31
5.4.3 [SDC-SUM-NOTIF] Default configuration of update notifications . 31
5.4.4 [SDC-FRM] Factory reset to restore the default state. 31
5.4.5 [SDC-PARCONT] Default configuration for parental control . 32
5.4.6 [SDC-MON-HANDLE] Handling of events by default . 32
5.4.7 [CRY-SOTA] State-of-the-art cryptography . 32
5.4.8 [CRY-CCK-PRE-LEN] Key size of preinstalled confidential cryptographic keys . 32
5.4.9 [CRY-CCK-GEN] Default key size of generated confidential cryptographic keys . 32
5.4.10 [CRY-PW-PRE-COM] Complexity of preinstalled passwords . 33
5.4.11 [CRY-PW-GEN-COM] Default complexity of generated passwords . 33
5.4.12 [CRY-PW-USR-COM] Recommended complexity of user chosen passwords . 33
5.5 Security updates . 33
5.5.0 Security updates introduction . 33
5.5.1 [SU-SUPPORT] Software update mechanism . 33
5.5.2 [SU-PROVIDE] Secure software update mechanism for core components . 33
5.5.3 [SU-AUTO] Automated security updates . 34
5.5.4 [SU-DISABLE-AUTO] Option to disable automated security updates . 34
5.5.5 [SU-POSTPONE-AUTO] Option to postpone automated security updates . 34
5.5.6 [SU-NOTIF] Update notifications . 34
5.6 Authentication and access control . 34
5.6.0 Authentication and access control introduction . 34
5.6.1 [ACM-FH] Access control for functions whose use can cause harm . 34
5.6.2 [AUM-FH] Authentication for functions whose use can cause harm . 35
5.6.3 [AUTHZ-LP] Least privilege in authorisation policies . 36
5.6.4 [AUTHZ-R] Revocability of granted permissions . 36
5.6.5 [PARCONT] Support of parental control . 36
5.6.6 [AUTHZ-PC] Authorisation policies for parental control . 37
5.7 Confidentiality protection . 37
5.7.0 Confidentiality protection introduction . 37
5.7.1 [CONF-SSM] Confidentiality protecting persistent storage for confidential data . 37
5.7.2 [CONF-COM] Communication of confidential data . 37
5.7.3 [CONF-MON-HW] Indication of active capture of audio or video data . 38
5.8 Integrity protection . 38
5.8.0 Integrity protection introduction . 38
5.8.1 [INT-SSM] Integrity protecting persistent storage for integrity relevant data . 38
5.8.2 [INT-SWPCK] Software package verification . 39
5.8.3 [INT-COM] Communication of integrity relevant data . 39
5.9 Data minimisation . 40
5.9.0 Data minimisation introduction . 40
5.9.1 [DMIN-DJST] Documented justification of processed data . 40
5.10 Availability protection . 40
5.10.0 Availability protection introduction . 40
5.10.1 [AVAI-TIME-RECO-POW] Restoration after loss of power . 40
5.10.2 [AVAI-TIME-NETW] Local operation . 40
5.10.3 [AVAI-TIME-RECO-NETW] Restoration after loss of network connection . 41
5.10.4 [AVAI-TIME-OUTA-NOT] Notify non-availability . 41
5.10.5 [AVAI-TIME-PREV-NOT] Notify upcoming limitation . 41
5.10.6 [AVAI-TIME-PREV-PRIO] Network prioritisation . 41
5.10.7 [AVAI-TIME-RES-PRIO] Power resource prioritisation . 41
5.10.8 [AVAI-UPD-SCHEDULE] Scheduling of updates . 42
5.11 Non-interference . 42
5.12 Attack surface minimisation . 42
5.12.0 Attack surface minimisation introduction . 42
5.12.1 [LAS-INVAL] Validation of external data input . 42
5.12.2 [LAS-INSAN] Sanitisation of external data input . 42
5.12.3 [LAS-PHY-INF] Only necessary physical interfaces . 42
ETSI
5 Draft ETSI EN 304 634 V1.0.0 (2026-07)
5.12.4 [LAS-LOGIC-INF] Only necessary logical interfaces active by default . 43
5.12.5 [LAS-SBOOT] Secure boot . 43
5.13 Exploit mitigation . 43
5.13.0 Exploit mitigation introduction . 43
5.13.1 [PRIV-DATA-HIGH] Privileged access on impact class high data assets . 43
5.13.2 [PRIV-FUNC-HIGH] Privileged access on impact class high function assets . 43
5.14 Monitoring . 43
5.14.0 Monitoring introduction . 43
5.14.1 [MON-LOW] Events to log for low risk personal wearable . 44
5.14.2 [MON-MEDIUM] Events to log for medium risk personal wearable . 44
5.14.3 [MON-HIGH] Events to log for high risk personal wearable . 44
5.14.4 [MON-HANDLE] Handling of events . 44
5.14.5 [LOG-TIME] Timestamps for logs . 44
5.14.6 [LOG-TIME-HIGH] Real-time timestamps for logs . 44
5.14.7 [LOG-STORE-MEDIUM] Logfile persistence for medium risk personal wearable . 45
5.14.8 [LOG-STORE-HIGH] Logfile persistence for high risk personal wearable. 45
5.14.9 [LOG-CONFIG] Configuration of logging mechanisms . 45
5.15 Factory reset and data portability . 45
5.15.0 Factory reset and data portability introduction . 45
5.15.1 [DLM-PERM] Permanent removal of user-related data . 46
6 Assessment criteria for compliance with technical requirements . 46
6.1 Introduction to the assessment and compliance criteria . 46
6.2 Appropriate level of cybersecurity . 47
6.2.1 Assessment criteria for [USERNOT-NOSE CFU C] . 47
6.2.2 Assessment criteria for [USERNOT-SECREL]. 48
6.2.3 Assessment criteria for [GUI-SECCONF] . 49
6.2.4 Assessment criteria for [BACKUP-TRANS]. 50
6.2.5 Assessment criteria for [BACKUP-AUTOTRANS] . 51
6.2.6 Assessment criteria for [BACKUP-EXPORT] . 52
6.3 No known exploitable vulnerabilities . 54
6.3.1 Assessment criteria for [NKEV-MKAV] . 54
6.3.2 Assessment criteria for [NKEV-INIT-UPD] . 55
6.4 Secure by default configuration . 56
6.4.1 Assessment criteria for [SDC-AUM-FH] . 56
6.4.2 Assessment criteria for [SDC-SUM-AUTO] . 57
6.4.3 Assessment criteria for [SDC-SUM-NOTIF] . 58
6.4.4 Assessment criteria for [SDC-FRM] . 59
6.4.5 Assessment criteria for [SDC-PARCONT] . 60
6.4.6 Assessment criteria for [SDC-MON-HANDLE] . 61
6.4.7 Assessment criteria for [CRY-SOTA] . 62
6.4.8 Assessment criteria for [CRY-CCK-PRE-LEN] . 62
6.4.9 Assessment criteria for [CRY-CCK-GEN] . 63
6.4.10 Assessment criteria for [CRY-PW-PRE-COM]. 64
6.4.11 Assessment criteria for [CRY-PW-GEN-COM] . 65
6.4.12 Assessment criteria for [CRY-PW-USR-COM] . 66
6.5 Security updates . 67
6.5.1 Assessment criteria for [SU-SUPPORT] . 67
6.5.2 Assessment criteria for [SU-PROVIDE] . 68
6.5.3 Assessment criteria for [SU-AUTO]. 69
6.5.4 Assessment criteria for [SU-DISABLE-AUTO] . 70
6.5.5 Assessment criteria for [SU-POSTPONE-AUTO] . 71
6.5.6 Assessment criteria for [SU-NOTIF] . 72
6.6 Authentication and access control . 73
6.6.1 Assessment criteria for [ACM-FH] . 73
6.6.2 Assessment criteria for [AUM-FH] . 75
6.6.3 Assessment criteria for [AUTHZ-LP]. 76
6.6.4 Assessment criteria for [AUTHZ-R]. 76
6.6.5 Assessment criteria for [PARCONT] . 77
6.6.6 Assessment criteria for [AUTHZ-PC] . 78
6.7 Confidentiality protection . 79
6.7.1 Assessment criteria for [CONF-SSM] . 79
ETSI
6 Draft ETSI EN 304 634 V1.0.0 (2026-07)
6.7.2 Assessment criteria for [CONF-COM] . 80
6.7.3 Assessment criteria for [CONF-MON-HW] . 82
6.8 Integrity protection . 83
6.8.1 Assessment criteria for [INT-SSM] . 83
6.8.2 Assessment criteria for [INT-SWPCK] . 84
6.8.3 Assessment criteria for [INT-COM] . 85
6.9 Data minimisation . 87
6.9.1 Assessment criteria for [DMIN-DJST] . 87
6.10 Availability protection . 87
6.10.1 Assessment criteria for [AVAI-TIME-RECO-POW] . 87
6.10.2 Assessment criteria for [AVAI-TIME-NETW] . 89
6.10.3 Assessment criteria for [AVAI-TIME-RECO-NETW] . 90
6.10.4 Assessment criteria for [AVAI-TIME-OUTA-NOT] . 92
6.10.5 Assessment criteria for [AVAI-TIME-PREV-NOT] . 93
6.10.6 Assessment criteria for [AVAI-TIME-RES-PRIO] . 95
6.10.7 Assessment criteria for [AVAI-TIME-RES-PRIO] . 96
6.10.8 Assessment criteria for [AVAI-SUM-SCHEDULE] . 97
6.11 Non-interference . 98
6.12 Attack surface minimisation . 98
6.12.1 Assessment criteria for [LAS-INVAL] . 98
6.12.2 Assessment criteria for [LAS-INSAN] . 99
6.12.3 Assessment criteria for [LAS-PHY-INF] . 100
6.12.4 Assessment criteria for [LAS-LOGIC-INF] . 101
6.12.5 Assessment criteria for [LAS-SBOOT] . 102
6.13 Exploit mitigation . 103
6.13.1 Assessment criteria for [PRIV-DATA-HIGH] . 103
6.13.2 Assessment criteria for [PRIV-FUNC-HIGH] . 104
6.14 Monitoring . 105
6.14.1 Assessment criteria for [MON-LOW] . 105
6.14.2 Assessment criteria for [MON-MEDIUM] . 106
6.14.3 Assessment criteria for [MON-HIGH] . 106
6.14.4 Assessment criteria for [MON-HANDLE] . 107
6.14.5 Assessment criteria for [LOG-TIME] . 108
6.14.6 Assessment criteria for [LOG-TIME-HIGH]. 109
6.14.7 Assessment criteria for [LOG-STORE-MEDIUM] . 110
6.14.8 Assessment criteria for [LOG-STORE-HIGH] . 111
6.14.9 Assessment criteria for [LOG-CONFIG] . 112
6.15 Factory reset and data portability . 114
6.15.1 Assessment criteria for [DLM-PERM] . 114
Annex A (informative): Relationship between the present document and the requirements of
EU Regulation 2024/2847 . 116
Annex B (informative): Security analysis . 121
B.1 General . 121
B.2 Assets . 121
B.3 Risk factors . 121
B.4 Assumptions . 121
B.5 Threats . 122
B.6 Relationship between the present document and the covered/not covered cybersecurity risks . 122
B.7 Guidance for determining impact classes . 126
B.7.1 General . 126
B.7.2 Confidential data . 126
B.7.3 loss sensitive data . 127
B.7.4 time sensitive data and time sensitive function . 127
B.7.5 integrity relevant data and integrity relevant function . 127
Annex C:            Void . 129
ETSI
7 Draft ETSI EN 304 634 V1.0.0 (2026-07)
Annex D (normative): Relationship between specific data and functions assets covered by
the present document to impact classes for generic asset categories. 130
D.1 Data assets . 130
D.2 Function assets . 131
D.2.1 Functions . 131
D.2.2 Functions whose use can cause harm . 131
Annex E (normative): Protection measures . 133
E.1 authentication mechanism strength . 133
E.1.1 [AUM-FH] Authentication for functions whose use can cause harm . 133
E.1.1.1 General . 133
E.1.1.2 [AUM-E-I-Basic] AUTH.Basic inherence based SFA . 133
E.1.1.3 [AUM-E-K-Basic] AUTH.Basic knowledge based SFA . 133
E.1.1.4 [AUM-E-I-Medium] AUTH.Medium inherence based SFA . 133
E.1.1.5 [AUM-E-K-Medium] AUTH.Medium knowledge based SFA . 133
E.1.1.6 [AUM-E-P-Medium] AUTH.Medium possession based SFA . 133
E.1.1.7 [AUM-E-MFA-Medium] AUTH.Medium MFA . 134
E.1.1.8 [AUM-E-I-Enhanced] AUTH.Enhanced inherence based SFA. 134
E.1.1.9 [AUM-E-K-Enhanced] AUTH.Enhanced knowledge based SFA . 134
E.1.1.10 [AUM-E-P-Enhanced] AUTH.Enhanced possession based SFA . 134
E.1.1.11 [AUM-E-MFA-Enhanced] AUTH.Enhanced MFA . 135
E.1.1.12 [AUM-E-I-Strong] AUTH.Strong inherence based SFA . 135
E.1.1.13 [AUM-E-P-Strong] AUTH.Strong possession based SFA . 135
E.1.1.14 [AUM-E-MFA-Strong] AUTH.Strong MFA . 135
E.1.1.15 [AUM-E-Replay] AUTH.Medium, AUTH.Enhanced and AUTH.Strong replay protection . 135
E.1.1.16 [AUM-E-PitM] AUTH.Medium, AUTH.Enhanced and AUTH.Strong person in the middle
protection . 136
E.1.2 Assessment for [AUM-FH] authentication mechanism strength . 136
E.1.2.1 General . 136
E.1.2.2 Assessment criteria for [AUM-E-I-Basic] . 136
E.1.2.3 Assessment criteria for [AUM-E-K-Basic] . 137
E.1.2.4 Assessment criteria for [AUM-E-I-Medium]. 138
E.1.2.5 Assessment criteria for [AUM-E-K-Medium] . 138
E.1.2.6 Assessment criteria for [AUM-E-P-Medium] . 139
E.1.2.7 Assessment criteria for [AUM-E-MFA-Medium] . 140
E.1.2.8 Assessment criteria for [AUM-E-I-Enhanced] . 141
E.1.2.9 Assessment criteria for [AUM-E-K-Enhanced] . 142
E.1.2.10 Assessment criteria for [AUM-E-P-Enhanced] . 143
E.1.2.11 Assessment criteria for [AUM-E-MFA-Enhanced] . 145
E.1.2.12 Assessment criteria for [AUM-E-I-Strong] . 146
E.1.2.13 Assessment criteria for [AUM-E-P-Strong] . 147
E.1.2.14 Assessment criteria for [AUM-E-MFA-Strong] . 148
E.1.2.15 Assessment criteria for [AUM-E-Replay] . 149
E.1.2.16 Assessment criteria for [AUM-E-PitM] . 150
E.2 integrity protection strength . 151
E.2.1 [INT-SSM] Integrity protecting persistent storage for integrity relevant data . 151
E.2.1.1 General . 151
E.2.1.2 [INT-SSM-E-Basic] INT.SSM.Basic integrity protecting secure storage mechanism . 151
E.2.1.3 [INT-SSM-E-Medium] INT.SSM.Medium integrity protecting secure storage mechanism . 152
E.2.1.4 [INT-SSM-E-Enhanced] INT.SSM.Enhanced integrity protecting secure storage mechanism . 152
E.2.1.5 [INT-SSM-E-Strong] INT.SSM.Strong integrity
...