IEC 62443-4-2:2019

IEC 62443-4-2 ®
Edition 1.0 2019-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Security for industrial automation and control systems –
Part 4-2: Technical security requirements for IACS components

Sécurité des systèmes d’automatisation et de commande industrielles –
Partie 4-2: Exigences de sécurité technique des composants IACS

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IEC 62443-4-2 ®
Edition 1.0 2019-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Security for industrial automation and control systems –

Part 4-2: Technical security requirements for IACS components

Sécurité des systèmes d’automatisation et de commande industrielles –

Partie 4-2: Exigences de sécurité technique des composants IACS

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 25.040.40; 35.030 ISBN 978-2-8322-6597-0

– 2 – IEC 62443-4-2:2019  IEC 2019
CONTENTS
FOREWORD . 12
INTRODUCTION . 14
1 Scope . 17
2 Normative references . 17
3 Terms, definitions, abbreviated terms, acronyms, and conventions . 18
3.1 Terms and definitions . 18
3.2 Abbreviated terms and acronyms . 24
3.3 Conventions . 26
4 Common component security constraints . 27
4.1 Overview. 27
4.2 CCSC 1: Support of essential functions . 27
4.3 CCSC 2: Compensating countermeasures . 27
4.4 CCSC 3: Least privilege . 27
4.5 CCSC 4: Software development process . 27
5 FR 1 – Identification and authentication control . 27
5.1 Purpose and SL-C(IAC) descriptions . 27
5.2 Rationale . 28
5.3 CR 1.1 – Human user identification and authentication . 28
5.3.1 Requirement . 28
5.3.2 Rationale and supplemental guidance. 28
5.3.3 Requirement enhancements . 28
5.3.4 Security levels . 29
5.4 CR 1.2 – Software process and device identification and authentication . 29
5.4.1 Requirement . 29
5.4.2 Rationale and supplemental guidance. 29
5.4.3 Requirement enhancements . 29
5.4.4 Security levels . 30
5.5 CR 1.3 – Account management . 30
5.5.1 Requirement . 30
5.5.2 Rationale and supplemental guidance. 30
5.5.3 Requirement enhancements . 30
5.5.4 Security levels . 30
5.6 CR 1.4 – Identifier management . 30
5.6.1 Requirement . 30
5.6.2 Rationale and supplemental guidance. 30
5.6.3 Requirement enhancements . 31
5.6.4 Security levels . 31
5.7 CR 1.5 – Authenticator management . 31
5.7.1 Requirement . 31
5.7.2 Rationale and supplemental guidance. 31
5.7.3 Requirement enhancements . 32
5.7.4 Security levels . 32
5.8 CR 1.6 – Wireless access management . 32

5.9 CR 1.7 – Strength of password-based authentication . 32
5.9.1 Requirement . 32
5.9.2 Rationale and supplemental guidance. 32
5.9.3 Requirement enhancements . 32
5.9.4 Security levels . 33
5.10 CR 1.8 – Public key infrastructure certificates . 33
5.10.1 Requirement . 33
5.10.2 Rationale and supplemental guidance. 33
5.10.3 Requirement enhancements . 33
5.10.4 Security levels . 33
5.11 CR 1.9 – Strength of public key-based authentication . 34
5.11.1 Requirement . 34
5.11.2 Rationale and supplemental guidance. 34
5.11.3 Requirement enhancements . 35
5.11.4 Security levels . 35
5.12 CR 1.10 – Authenticator feedback . 35
5.12.1 Requirement . 35
5.12.2 Rationale and supplemental guidance. 35
5.12.3 Requirement enhancements . 35
5.12.4 Security levels . 35
5.13 CR 1.11 – Unsuccessful login attempts . 35
5.13.1 Requirement . 35
5.13.2 Rationale and supplemental guidance. 36
5.13.3 Requirement enhancements . 36
5.13.4 Security levels . 36
5.14 CR 1.12 – System use notification . 36
5.14.1 Requirement . 36
5.14.2 Rationale and supplemental guidance. 36
5.14.3 Requirement enhancements . 36
5.14.4 Security levels . 37
5.15 CR 1.13 – Access via untrusted networks . 37
5.16 CR 1.14 – Strength of symmetric key-based authentication . 37
5.16.1 Requirement . 37
5.16.2 Rationale and supplemental guidance. 37
5.16.3 Requirement enhancements . 37
5.16.4 Security levels . 38
6 FR 2 – Use control. 38
6.1 Purpose and SL-C(UC) descriptions . 38
6.2 Rationale . 38
6.3 CR 2.1 – Authorization enforcement . 38
6.3.1 Requirement . 38
6.3.2 Rationale and supplemental guidance. 38
6.3.3 Requirement enhancements . 39
6.3.4 Security levels . 39
6.4 CR 2.2 – Wireless use control . 40
6.4.1 Requirement . 40
6.4.2 Rationale and supplemental guidance. 40
6.4.3 Requirement enhancements . 40
6.4.4 Security levels . 40

– 4 – IEC 62443-4-2:2019  IEC 2019
6.5 CR 2.3 – Use control for portable and mobile devices . 40
6.6 CR 2.4 – Mobile code. 40
6.7 CR 2.5 – Session lock . 40
6.7.1 Requirement . 40
6.7.2 Rationale and supplemental guidance. 41
6.7.3 Requirement enhancements . 41
6.7.4 Security levels . 41
6.8 CR 2.6 – Remote session termination . 41
6.8.1 Requirement . 41
6.8.2 Rationale and supplemental guidance. 41
6.8.3 Requirement enhancements . 41
6.8.4 Security levels . 41
6.9 CR 2.7 – Concurrent session control . 41
6.9.1 Requirement . 41
6.9.2 Rationale and supplemental guidance. 42
6.9.3 Requirement enhancements . 42
6.9.4 Security levels . 42
6.10 CR 2.8 – Auditable events . 42
6.10.1 Requirement . 42
6.10.2 Rationale and supplemental guidance. 42
6.10.3 Requirement enhancements . 42
6.10.4 Security levels . 43
6.11 CR 2.9 – Audit storage capacity . 43
6.11.1 Requirement . 43
6.11.2 Rationale and supplemental guidance. 43
6.11.3 Requirement enhancements . 43
6.11.4 Security levels . 43
6.12 CR 2.10 – Response to audit processing failures . 43
6.12.1 Requirement . 43
6.12.2 Rationale and supplemental guidance. 44
6.12.3 Requirement enhancements . 44
6.12.4 Security levels . 44
6.13 CR 2.11 – Timestamps . 44
6.13.1 Requirement . 44
6.13.2 Rationale and supplemental guidance. 44
6.13.3 Requirement enhancements . 44
6.13.4 Security levels . 44
6.14 CR 2.12 – Non-repudiation . 45
6.14.1 Requirement . 45
6.14.2 Rationale and supplemental guidance. 45
6.14.3 Requirement enhancements . 45
6.14.4 Security levels . 45
6.15 CR 2.13 – Use of physical diagnostic and test interfaces . 45
7 FR 3 – System integrity . 45
7.1 Purpose and SL-C(SI) descriptions . 45
7.2 Rationale . 46

7.3 CR 3.1 – Communication integrity . 46
7.3.1 Requirement . 46
7.3.2 Rationale and supplemental guidance. 46
7.3.3 Requirement enhancements . 47
7.3.4 Security levels . 47
7.4 CR 3.2 – Protection from malicious code . 47
7.5 CR 3.3 – Security functionality verification . 47
7.5.1 Requirement . 47
7.5.2 Rationale and supplemental guidance. 47
7.5.3 Requirement enhancements . 47
7.5.4 Security levels . 48
7.6 CR 3.4 – Software and information integrity . 48
7.6.1 Requirement . 48
7.6.2 Rationale and supplemental guidance. 48
7.6.3 Requirement enhancements . 48
7.6.4 Security levels . 48
7.7 CR 3.5 – Input validation . 48
7.7.1 Requirement . 48
7.7.2 Rationale and supplemental guidance. 49
7.7.3 Requirement enhancements . 49
7.7.4 Security levels . 49
7.8 CR 3.6 – Deterministic output . 49
7.8.1 Requirement . 49
7.8.2 Rationale and supplemental guidance. 49
7.8.3 Requirement enhancements . 49
7.8.4 Security levels . 50
7.9 CR 3.7 – Error handling . 50
7.9.1 Requirement . 50
7.9.2 Rationale and supplemental guidance. 50
7.9.3 Requirement enhancements . 50
7.9.4 Security levels . 50
7.10 CR 3.8 – Session integrity. 50
7.10.1 Requirement . 50
7.10.2 Rationale and supplemental guidance. 51
7.10.3 Requirement enhancements . 51
7.10.4 Security levels . 51
7.11 CR 3.9 – Protection of audit information . 51
7.11.1 Requirement . 51
7.11.2 Rationale and supplemental guidance. 51
7.11.3 Requirement enhancements . 51
7.11.4 Security levels . 51
7.12 CR 3.10 – Support for updates . 52
7.13 CR 3.11 – Physical tamper resistance and detection . 52
7.14 CR 3.12 – Provisioning product supplier roots of trust . 52
7.15 CR 3.13 – Provisioning asset owner roots of trust . 52
7.16 CR 3.14 – Integrity of the boot process . 52
8 FR 4 – Data confidentiality. 52
8.1 Purpose and SL-C(DC) descriptions . 52
8.2 Rationale . 52

– 6 – IEC 62443-4-2:2019  IEC 2019
8.3 CR 4.1 – Information confidentiality . 52
8.3.1 Requirement . 52
8.3.2 Rationale and supplemental guidance. 53
8.3.3 Requirement enhancements . 53
8.3.4 Security levels . 53
8.4 CR 4.2 – Information persistence . 53
8.4.1 Requirement . 53
8.4.2 Rationale and supplemental guidance. 53
8.4.3 Requirement enhancements . 53
8.4.4 Security levels . 54
8.5 CR 4.3 – Use of cryptography . 54
8.5.1 Requirement . 54
8.5.2 Rationale and supplemental guidance. 54
8.5.3 Requirement enhancements . 54
8.5.4 Security levels . 54
9 FR 5 – Restricted data flow . 55
9.1 Purpose and SL-C(RDF) descriptions . 55
9.2 Rationale . 55
9.3 CR 5.1 – Network segmentation . 55
9.3.1 Requirement . 55
9.3.2 Rationale and supplemental guidance. 55
9.3.3 Requirement enhancements . 56
9.3.4 Security levels . 56
9.4 CR 5.2 – Zone boundary protection . 56
9.5 CR 5.3 – General-purpose person-to-person communication restrictions . 56
9.6 CR 5.4 – Application partitioning . 56
10 FR 6 – Timely response to events. 56
10.1 Purpose and SL-C(TRE) descriptions . 56
10.2 Rationale . 57
10.3 CR 6.1 – Audit log accessibility . 57
10.3.1 Requirement . 57
10.3.2 Rationale and supplemental guidance. 57
10.3.3 Requirement enhancements . 57
10.3.4 Security levels . 57
10.4 CR 6.2 – Continuous monitoring . 57
10.4.1 Requirement . 57
10.4.2 Rationale and supplemental guidance. 57
10.4.3 Requirement enhancements . 58
10.4.4 Security levels . 58
11 FR 7 – Resource availability . 58
11.1 Purpose and SL-C(RA) descriptions . 58
11.2 Rationale . 58
11.3 CR 7.1 – Denial of service protection . 59
11.3.1 Requirement . 59
11.3.2 Rationale and supplemental guidance. 59
11.3.3 Requirement enhancements . 59
11.3.4 Security levels . 59

11.4 CR 7.2 – Resource management . 59
11.4.1 Requirement . 59
11.4.2 Rationale and supplemental guidance. 59
11.4.3 Requirement enhancements . 59
11.4.4 Security levels . 59
11.5 CR 7.3 – Control system backup . 60
11.5.1 Requirement . 60
11.5.2 Rationale and supplemental guidance. 60
11.5.3 Requirement enhancements . 60
11.5.4 Security levels . 60
11.6 CR 7.4 – Control system recovery and reconstitution . 60
11.6.1 Requirement . 60
11.6.2 Rationale and supplemental guidance. 60
11.6.3 Requirement enhancements . 60
11.6.4 Security levels . 61
11.7 CR 7.5 – Emergency power . 61
11.8 CR 7.6 – Network and security configuration settings . 61
11.8.1 Requirement . 61
11.8.2 Rationale and supplemental guidance. 61
11.8.3 Requirement enhancements . 61
11.8.4 Security levels . 61
11.9 CR 7.7 – Least functionality . 61
11.9.1 Requirement . 61
11.9.2 Rationale and supplemental guidance. 61
11.9.3 Requirement enhancements . 62
11.9.4 Security levels . 62
11.10 CR 7.8 – Control system component inventory . 62
11.10.1 Requirement . 62
11.10.2 Rationale and supplemental guidance. 62
11.10.3 Requirement enhancements . 62
11.10.4 Security levels . 62
12 Software application requirements . 62
12.1 Purpose . 62
12.2 SAR 2.4 – Mobile code . 62
12.2.1 Requirement . 62
12.2.2 Rationale and supplemental guidance. 63
12.2.3 Requirement enhancements . 63
12.2.4 Security levels . 63
12.3 SAR 3.2 – Protection from malicious code . 63
12.3.1 Requirement . 63
12.3.2 Rationale and supplemental guidance. 63
12.3.3 Requirement enhancements . 63
12.3.4 Security levels . 63
13 Embedded device requirements . 64
13.1 Purpose . 64
13.2 EDR 2.4 – Mobile code . 64
13.2.1 Requirement . 64
13.2.2 Rationale and supplemental guidance. 64
13.2.3 Requirement enhancements . 64

– 8 – IEC 62443-4-2:2019  IEC 2019
13.2.4 Security levels . 64
13.3 EDR 2.13 – Use of physical diagnostic and test interfaces . 64
13.3.1 Requirement . 64
13.3.2 Rationale and supplemental guidance. 65
13.3.3 Requirement enhancements . 65
13.3.4 Security levels . 65
13.4 EDR 3.2 – Protection from malicious code . 65
13.4.1 Requirement . 65
13.4.2 Rationale and supplemental guidance. 65
13.4.3 Requirement enhancements . 66
13.4.4 Security levels . 66
13.5 EDR 3.10 – Support for updates . 66
13.5.1 Requirement . 66
13.5.2 Rationale and supplemental guidance. 66
13.5.3 Requirement enhancements . 66
13.5.4 Security levels . 66
13.6 EDR 3.11 – Physical tamper resistance and detection . 66
13.6.1 Requirement . 66
13.6.2 Rationale and supplemental guidance. 66
13.6.3 Requirement enhancements . 67
13.6.4 Security levels . 67
13.7 EDR 3.12 – Provisioning product supplier roots of trust. 67
13.7.1 Requirement . 67
13.7.2 Rationale and supplemental guidance. 67
13.7.3 Requirement enhancements . 67
13.7.4 Security levels . 68
13.8 EDR 3.13 – Provisioning asset owner roots of trust . 68
13.8.1 Requirement . 68
13.8.2 Rationale and supplemental guidance. 68
13.8.3 Requirement enhancements . 68
13.8.4 Security levels . 68
13.9 EDR 3.14 – Integrity of the boot process . 69
13.9.1 Requirement . 69
13.9.2 Rationale and supplemental guidance. 69
13.9.3 Requirement enhancements . 69
13.9.4 Security levels . 69
14 Host device requirements . 69
14.1 Purpose . 69
14.2 HDR 2.4 – Mobile code . 69
14.2.1 Requirement . 69
14.2.2 Rationale and supplemental guidance. 70
14.2.3 Requirement enhancements . 70
14.2.4 Security levels . 70
14.3 HDR 2.13 – Use of physical diagnostic and test interfaces . 70
14.3.1 Requirement . 70
14.3.2 Rationale and supplemental guidance.
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