ETSI TS 133 501 V15.7.0 (2020-01)

ETSI TS 133 501 V15.7.0 (2020-01)






TECHNICAL SPECIFICATION
5G;
Security architecture and procedures for 5G System
(3GPP TS 33.501 version 15.7.0 Release 15)

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3GPP TS 33.501 version 15.7.0 Release 15 1 ETSI TS 133 501 V15.7.0 (2020-01)



Reference
RTS/TSGS-0333501vf70
Keywords
5G,SECURITY
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3GPP TS 33.501 version 15.7.0 Release 15 2 ETSI TS 133 501 V15.7.0 (2020-01)
Intellectual Property Rights
Essential patents
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ETSI

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3GPP TS 33.501 version 15.7.0 Release 15 3 ETSI TS 133 501 V15.7.0 (2020-01)
Contents
Intellectual Property Rights . 2
Legal Notice . 2
Modal verbs terminology . 2
Foreword . 12
1 Scope . 13
2 References . 13
3 Definitions and abbreviations . 15
3.1 Definitions . 15
3.2 Abbreviations . 19
4 Overview of security architecture . 20
4.1 Security domains . 20
4.2 Security entity at the perimeter of the 5G Core network . 21
4.3 Security entities in the 5G Core network . 21
5 Security requirements and features . 21
5.1 General security requirements . 21
5.1.1 Mitigation of bidding down attacks . 21
5.1.2 Authentication and Authorization . 21
5.1.3 Requirements on 5GC and NG-RAN related to keys . 22
5.2 Requirements on the UE . 22
5.2.1 General . 22
5.2.2 User data and signalling data confidentiality . 22
5.2.3 User data and signalling data integrity . 23
5.2.4 Secure storage and processing of subscription credentials . 23
5.2.5 Subscriber privacy . 24
5.3 Requirements on the gNB . 24
5.3.1 General . 24
5.3.2 User data and signalling data confidentiality . 24
5.3.3 User data and signalling data integrity . 25
5.3.4 Requirements for the gNB setup and configuration . 25
5.3.5 Requirements for key management inside the gNB . 26
5.3.6 Requirements for handling user plane data for the gNB . 26
5.3.7 Requirements for handling control plane data for the gNB . 26
5.3.8 Requirements for secure environment of the gNB . 26
5.3.9 Requirements for the gNB F1 interfaces. 26
5.3.10 Requirements for the gNB E1 interfaces . 27
5.4 Requirements on the ng-eNB . 27
5.5 Requirements on the AMF . 27
5.5.1 Signalling data confidentiality . 27
5.5.2 Signalling data integrity . 27
5.5.3 Subscriber privacy . 27
5.6 Requirements on the SEAF . 28
5.7 Void . 28
5.8 Requirements on the UDM . 28
5.8.1 Generic requirements . 28
5.8.2 Subscriber privacy related requirements to UDM and SIDF . 28
5.8a Requirements on AUSF . 28
5.9 Core network security . 28
5.9.1 Trust boundaries . 28
5.9.2 Requirements on service-based architecture . 29
5.9.2.1 Security Requirements for service registration, discovery and authorization . 29
5.9.2.2 NRF security requirements . 29
5.9.2.3 NEF security requirements . 29
5.9.3 Requirements for e2e core network interconnection security . 29
ETSI

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3GPP TS 33.501 version 15.7.0 Release 15 4 ETSI TS 133 501 V15.7.0 (2020-01)
5.9.3.1 General . 29
5.9.3.2 Requirements for Security Edge Protection Proxy (SEPP) . 30
5.9.3.3 Protection of attributes . 30
5.10 Visibility and configurability . 31
5.10.1 Security visibility . 31
5.10.2 Security configurability . 31
5.11 Requirements for algorithms, and algorithm selection . 31
5.11.1 Algorithm identifier values . 31
5.11.1.1 Ciphering algorithm identifier values. 31
5.11.1.2 Integrity algorithm identifier values . 32
5.11.2 Requirements for algorithm selection . 32
6 Security procedures between UE and 5G network functions . 33
6.0 General . 33
6.1 Primary authentication and key agreement . 33
6.1.1 Authentication framework . 33
6.1.1.1 General . 33
6.1.1.2 EAP fra me wor k . 34
6.1.1.3 Granularity of anchor key binding to serving network. 34
6.1.1.4 Construction of the serving network name . 34
6.1.1.4.1 Serving network name . 34
6.1.1.4.2 Construction of the serving network name by the UE . 34
6.1.1.4.3 Construction of the serving network name by the SEAF . 35
6.1.2 Initiation of authentication and selection of authentication method . 35
6.1.3 Authentication procedures . 36
6.1.3.1 Authentication procedure for EAP-AKA' . 36
6.1.3.2 Authentication procedure for 5G AKA . 39
6.1.3.2.0 5G AKA . 39
6.1.3.2.1 Void . 41
6.1.3.2.2 RES* verification failure in SEAF or AUSF or both . 41
6.1.3.3 Synchronization failure or MAC failure . 42
6.1.3.3.1 Synchronization failure or MAC failure in USIM . 42
6.1.3.3.2 Synchronization failure recovery in Home Network . 42
6.1.4 Linking increased home control to subsequent procedures . 43
6.1.4.1 Introduction . 43
6.1.4.1a Linking authentication confirmation to Nudm_UECM_Registration procedure from AMF . 43
6.1.4.2 Guidance on linking authentication confirmation to Nudm_UECM_Registration procedure from
AMF . 44
6.2 Key hierarchy, key derivation, and distribution scheme . 45
6.2.1 Key hierarchy . 45
6.2.2 Key derivation and distribution scheme . 47
6.2.2.1 Keys in network entities . 47
6.2.2.2 Keys in the UE . 48
6.2.3 Handling of user-related keys . 50
6.2.3.1 Key setting . 50
6.2.3.2 Key identification . 50
6.2.3.3 Key lifetimes . 51
6.3 Security contexts . 52
6.3.1 Distribution of security contexts . 52
6.3.1.1 General . 52
6.3.1.2 Distribution of subscriber identities and security data within one 5G serving network domain . 52
6.3.1.3 Distribution of subscriber identities and security data between 5G serving network domains . 52
6.3.1.4 Distribution of subscriber identities and security data between 5G and EPS serving network
domains . 52
6.3.2 Multiple registrations in same or different serving networks . 53
6.3.2.0 General . 53
6.3.2.1 Multiple registrations in different PLMNs . 53
6.3.2.2 Multiple registrations in the same PLMN . 53
6.4 NAS security mechanisms . 53
6.4.1 General . 53
6.4.2 Security for multiple NAS connections . 53
6.4.2.1 Multiple active NAS connections with different PLMNs . 53
ETSI

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3GPP TS 33.501 version 15.7.0 Release 15 5 ETSI TS 133 501 V15.7.0 (2020-01)
6.4.2.2 Multiple active NAS connections in the same PLMN's serving network . 54
6.4.3 NAS integrity mechanisms . 55
6.4.3.0 General . 55
6.4.3.1 NAS input parameters to integrity algorithm . 55
6.4.3.2 NAS integrity activation . 55
6.4.3.3 NAS integrity failure handling . 55
6.4.4 NAS confidentiality mechanisms . 56
6.4.4.0 General . 56
6.4.4.1 NAS input parameters to confidentiality algorithm . 56
6.4.4.2 NAS confidentiality activation . 56
6.4.5 Handling of NAS COUNTs . 56
6.4.6 Protection of initial NAS message . 56
6.4.7 Security aspects of SMS over NAS . 58
6.5 RRC security mechanisms . 58
6.5.1 RRC integrity mechanisms . 58
6.5.2 RRC confidentiality mechanisms . 58
6.5.3 RRC UE capability transfer procedure . 58
6.6 UP security mechanisms . 59
6.6.1 UP security policy . 59
6.6.2 UP security activation mechanism . 60
6.6.3 UP confidentiality mechanisms . 61
6.6.4 UP integrity mechanisms . 61
6.7 Security algorithm selection, key establishment and security mode command procedure . 61
6.7.1 Procedures for NAS algorithm selection . 61
6.7.1.1 Initial NAS security context establishment . 61
6.7.1.2 AMF change . 61
6.7.2 NAS security mode command procedure . 62
6.7.3 Procedures for AS algorithm selection . 63
6.7.3.0 Initial AS security context establishment . 63
6.7.3.1 Xn-handover. 64
6.7.3.2 N2-handover. 64
6.7.3.3 Intra-gNB-CU handover/intra-ng-eNB handover. 64
6.7.3.4 Transitions from RRC_INACTIVE to RRC_CONNECTED states . 64
6.7.3.5 RNA Update procedure . 65
6.7.3.6 Algorithm negotiation for unauthenticated UEs in LSM . 65
6.7.4 AS security mode command procedure . 65
6.8 Security handling in state transitions . 67
6.8.1 Key handling at connection and registration state transitions . 67
6.8.1.1 Key handling at transitions between RM-DEREGISTERED and RM-REGISTERED states . 67
6.8.1.1.0 General . 67
6.8.1.1.1 Transition from RM-REGISTERED to RM-DEREGISTERED . 67
6.8.1.1.2 Transition from RM-DEREGISTERED to RM-REGISTERED . 68
6.8.1.1.2.1 General . 68
6.8.1.1.2.2 Full native 5G NAS security context available . 68
6.8.1.1.2.3 Full native 5G NAS security context not available . 69
6.8.1.1.2.4 UE registration over a second access type to the same AMF . 69
6.8.1.2 Key handling at transitions between CM-IDLE and CM-CONNECTED states . 70
6.8.1.2.0 General . 70
6.8.1.2.1 Transition from CM-IDLE to CM-CONNECTED . 70
6.8.1.2.2 Establishment of keys for cryptographically protected radio bearers in 3GPP access . 70
6.8.1.2.3 Establishment of keys for cryptographically protected traffic in non-3GPP a
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