ETSI TR 133 926 V17.9.0 (2024-04)

LTE; 5G; Security Assurance Specification (SCAS) threats and critical assets in 3GPP network product classes (3GPP TR 33.926 version 17.9.0 Release 17)

RTR/TSGS-0333926vh90

General Information

• Status: Not Published
• Technical Committee: 3GPP SA 3 - Security
• Current Stage: 12 - Citation in the OJ (auto-insert)
• Completion Date: 22-Apr-2024

Standards Content (Sample)

TECHNICAL REPORT
LTE;
5G;
Security Assurance Specification (SCAS) threats and
critical assets in 3GPP network product classes
(3GPP TR 33.926 version 17.9.0 Release 17)

3GPP TR 33.926 version 17.9.0 Release 17 1 ETSI TR 133 926 V17.9.0 (2024-04)

Reference
RTR/TSGS-0333926vh90
Keywords
5G,LTE
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ETSI
3GPP TR 33.926 version 17.9.0 Release 17 2 ETSI TR 133 926 V17.9.0 (2024-04)
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ETSI
3GPP TR 33.926 version 17.9.0 Release 17 3 ETSI TR 133 926 V17.9.0 (2024-04)
Contents
Intellectual Property Rights . 2
Legal Notice . 2
Modal verbs terminology . 2
Foreword . 10
1 Scope . 11
2 References . 11
3 Definitions and abbreviations . 12
3.1 Definitions . 12
3.2 Abbreviations . 12
4 Generic Network Product (GNP) class description . 13
4.1 Overview . 13
4.2 Minimum set of functions defining the GNP class . 14
4.3 Generic network product model . 14
4.3.1 Generic network product model overview . 14
4.3.2 Functions defined by 3GPP . 14
4.3.3 Other functions . 14
4.3.4 Operating System (OS) . 14
4.3.5 Hardware . 14
4.3.6 Interfaces. 15
4.4 Scope of the present document . 15
4.4.1 Introduction. 15
4.4.2 Scope regarding GNP functions defined by 3GPP . 16
4.4.3 Scope regarding other functions . 16
4.4.4 Scope regarding Operating System (OS) . 16
4.4.5 Scope regarding hardware . 16
4.4.6 Scope regarding interfaces . 16
5 Generic assets and threats . 16
5.1 Introduction . 16
5.2 Generic critical assets . 16
5.3 Generic threats . 17
5.3.0 Generic threats format . 17
5.3.1 Introduction. 17
5.3.2 Threats relating to 3GPP-defined interfaces . 18
5.3.3 Spoofing identity . 18
5.3.3.1 Default Accounts . 18
5.3.3.2 Weak Password Policies . 18
5.3.3.3 Password peek . 19
5.3.3.4 Direct Root Access . 19
5.3.3.5 IP Spoofing . 19
5.3.3.6 Malware . 19
5.3.3.7 Eavesdropping . 19
5.3.4 Tampering . 20
5.3.4.1 Software Tampering . 20
5.3.4.2 Ownership File Misuse . 20
5.3.4.3 External Device Boot . 20
5.3.4.4 Log Tampering . 20
5.3.4.5 OAM Traffic Tampering . 20
5.3.4.6 File Write Permissions Abuse . 21
5.3.4.7 User Session Tampering . 21
5.3.5 Repudiation . 21
5.3.5.1 Lack of User Activity Trace . 21
5.3.6 Information disclosure . 21
5.3.6.1 Poor key generation. 21
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5.3.6.2 Poor key management . 22
5.3.6.3 Weak cryptographic algorithms . 22
5.3.6.4 Insecure Data Storage . 22
5.3.6.5 System Fingerprinting . 22
5.3.6.6 Malware . 22
5.3.6.7 Personal Identification Information Violation. 23
5.3.6.8 Insecure Default Configuration . 23
5.3.6.9 File/Directory Read Permissions Misuse . 23
5.3.6.10 Insecure Network Services . 23
5.3.6.11 Unnecessary Services . 23
5.3.6.12 Log Disclosure . 24
5.3.6.13 Unnecessary Applications . 24
5.3.6.14 Eavesdropping . 24
5.3.6.15 Security threat caused by lack of GNP traffic isolation . 24
5.3.7 Denial of service . 25
5.3.7.1 Compromised/Misbehaving User Equipments . 25
5.3.7.2 Implementation Flaw . 25
5.3.7.3 Insecure Network Services . 25
5.3.7.4 Human Error . 25
5.3.8 Elevation of privilege. 26
5.3.8.1 Misuse by authorized users . 26
5.3.8.2 Over-Privileged Processes/Services . 26
5.3.8.3 Folder Write Permission Abuse . 26
5.3.8.4 Root-Owned File Write Permission Abuse . 26
5.3.8.5 High-Privileged Files . 26
5.3.8.6 Insecure Network Services . 27
5.3.8.7 Elevation of Privilege via Unnecessary Network Services . 27
6 Generic assets and threats for network functions supporting SBA interfaces . 27
6.1 Introduction . 27
6.2 Generic critical assets . 27
6.3 Generic threats . 28
6.3.1 Introduction. 28
6.3.2 Threats related to Service Based Interfaces . 28
6.3.2.1 JSON Parser Exploits . 28
6.3.2.2 JSON Parser not Robust . 28
6.3.3 Threats related to service access . 28
6.3.3.1 Elevation of privilege via incorrect verification of access tokens . 28
6.3.4 Threats related to authentication for indirect communication . 29
6.3.4.1 Incorrect validation of client credentials assertion . 29
Annex A:  Aspects specific to the network product class MME . 30
A.1 Network product class description for the MME . 30
A.1.1 Introduction . 30
A.1.2 Minimum set of functions defining the MME network product class . 30
A.2 Assets and threats specific to the MME . 30
A.2.1 Critical assets . 30
A.2.2 Threats related to AKA procedures . 31
A.2.2.1 Access to 2G . 31
A.2.2.2 Resynchronization . 31
A.2.2.3 Failed Integrity check of Attach message . 31
A.2.2.4 Forwarding EPS authentication data to SGSN . 31
A.2.2.5 Forwarding unused EPS authentication data between different security domains . 31
A.2.3 Threats related to security mode command procedure . 32
A.2.3.1 Bidding Down . 32
A.2.3.2 NAS integrity selection and use . 32
A.2.3.3 NAS NULL integrity protection . 32
A.2.3.4 NAS confidentiality protection . 32
A.2.4 Threats related to security in Intra-RAT mobility . 32
A.2.4.1 Bidding down on X2-Handover . 32
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A.2.4.2 NAS integrity protection algorithm selection in MME change . 33
A.2.5 Threats related to security in Inter-RAT mobility . 33
A.2.5.1 2G SIM access via idle mode mobility . 33
A.2.5.2 2G SIM access via handover. 33
A.2.5.3 2G SIM access via SRVCC . 33
A.2.6 Threats related to release of non-emergency bearer . 33
Annex B:  Aspects specific to the network product class PGW . 35
B.1 Network product class description for the PGW . 35
B.1.1 Introduction . 35
B.1.2 Minimum set of functions defining the PGW network product class . 35
B.2 Assets and threats specific to the PGW . 35
B.2.1 Critical assets . 35
B.2.2 Threats related to IP Address Allocation . 36
B.2.2.1 IP Address Reallocation Continuously . 36
B.2.3 Packet Forwarding . 36
B.2.3.1 Sending unauthorized packets to other UEs . 36
B.2.4 Emergency PDN Connection . 36
B.2.4.1 Inactive Emergency PDN Connection Release . 36
B.2.5 Threats related to charging relevant data . 36
B.2.5.1 Failure to assign unique TEID or Charging ID for a session . 36
Annex C: Aspects specific to the network product class eNB . 38
C.1 Network product class description for the eNB . 38
C.1.1 Introduction. 38
C.1.2 Minimum set of functions defining the eNB network product class . 38
C.2 Assets and threats specific to the eNB . 38
C.2.1 Critical assets . 38
C.2.2 Threats related to Control plane and User plane . 39
C.2.2.1 Control plane data confidentiality protection . 39
C.2.2.2 Control plane data integrity protection . 39
C.2.2.3 User plane data ciphering and deciphering at eNB . 39
C.2.2.4 User plane data integrity protection . 39
C.2.3 Threats related to key reuse . 40
C.2.3.1 Key reuse for eavesdropping . 40
Annex D:  Aspects specific to the network product class gNB . 41
D.1 Network product class description for the gNB . 41
D.1.1 Introduction. 41
D.1.2 Minimum set of functions defining the gNB network product class . 41
D.2 Assets and threats specific to the gNB . 41
D.2.1 Critical assets . 41
D.2.2 Threats related to Control plane and User plane in the network. 42
D.2.2.1 Control plane data confidentiality protection . 42
D.2.2.2 Control plane data integrity protection . 42
D.2.2.3 User plane data confidentiality protection at gNB . 42
D.2.2.4 User plane data integrity protection . 42
D.2.2. 5 AS algorithm selection and use. 43
D.2.2.6 Bidding down on Xn-Handover . 43
D.2.2.7 Key Reuse . 43
D.2.2.8 Security Policy Enforcement . 43
D.2.2.9 State transition from inactive state to connected state . 43
Annex E:  Aspects specific to the network product class UDM . 45
E.1 Network product class description for the UDM . 45
E.1.1 Introduction . 45
E.1.2 Minimum set of functions defining the UDM network product class . 45
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E.2 Assets and threats specific to the UDM . 45
E.2.1 Critical assets . 45
E.2.2 Threats related to UDM assets . 46
E.2.2.1 Incorrect SUCI de-concealment . 46
E.2.2.2 Synchronization failure . 46
E.2.2.3 Failure to store the authentication status . 46
E.2.2.4 Incorrect security enforcement configuration . 46
E.2.2.5 Incorrect UP security policy configuration for 5G LAN service . 46
Annex F:  Aspects specific to the network product class AUSF . 48
F.1 Network product class description for the AUSF . 48
F.1.1 Introduction. 48
F.1.2 Minimum set of functions defining the AUSF network product class . 48
F.2 Assets and threats specific to the AUSF. 48
F.2.1 Critical assets . 48
F.2.2 Threats related to authentication procedures . 49
Annex G:  Aspects specific to the network product class SEPP . 50
G.1 Network product class description for the SEPP . 50
G.1.1 Introduction . 50
G.1.2 Minimum set of functions defining the SEPP network product class . 50
G.2 Assets and threats specific to the SEPP . 50
G.2.1 Critical assets . 50
G.2.2 Threats related to cryptographic material in the SEPP . 51
G.2.2.1 Misusing cryptographic material of peer SEPPs and IPX providers . 51
G.2.2.2 Misusing cryptographic material beyond connection-specific scope . 51
G.2.3 Threats related to error handling in the SEPP . 51
G.2.3.1 Incorrect handling for PLMN ID mismatch . 51
G.2.3.2 Incorrect handling for protection policies mismatch . 52
G.2.4 Threats related to sensitive information exposure . 52
G.2.4.1 Weak JWS algorithm . 52
G.2.4.2 Exposure of confidential IEs in N32-f message . 53
G.2.5 Threats related to TLS protection between NF and SEPP . 53
G.2.5.1 Inter-PLMN routing using the incorrect reference . 53
G.2.5.2 Tampering of Target API Root . 53
Annex H:  Aspects specific to the network product class NRF . 55
H.1 Network product class description for the NRF . 55
H.1.1 Introduction . 55
H.1.2 Minimum set of functions defining the NRF network product class . 55
H.2 Assets and threats specific to the NRF . 55
H.2.1 Critical assets . 55
H.2.2 Threats related to NRF authorization . 56
H.2.2.1 No slice specific authorization for NF discovery . 56
Annex I:  Aspects specific to the network product class NEF . 57
I.1 Network product class description for the NEF . 57
I.1.1 Introduction. 57
I.1.2 Minimum set of functions defining the NEF network product class . 57
I.2 Assets and threats specific to the NEF . 57
I.2.1 Critical assets . 57
I.2.2 Threats related to NEF assets . 58
I.2.2.1 No authentication on application function . 58
I.2.2.2 No authorization on northbound APIs . 58
Annex J:  Aspects specific to the network product class SMF . 59
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J.1 Network product class description for the SMF . 59
J.1.1 Introduction. 59
J.1.2 Minimum set of functions defining the SMF network product class . 59
J.2 Assets and threats specific to the SMF . 59
J.2.1 Critical assets . 59
J.2.2 Threats related to SMF assets . 60
J.2.2.1 Priority of UP security policy . 60
J.2.2.2 TEID uniqueness failure . 60
J.2.2.3 Charging ID Uniqueness failure . 60
J.2.2.3 UP security policy check . 60
Annex K:  Aspects specific to the network product class AMF . 61
K.1 Network product class description for the AMF . 61
K.1.1 Introduction . 61
K.1.2 Minimum set of functions defining the AMF network product class . 61
K.2 Assets and threats specific to the AMF . 61
K.2.1 Critical assets . 61
K.2.2 Threats related to AKA procedures . 62
K.2.2.1 Resynchronization . 62
K.2.2.2 Failed Integrity check of Initial Registration message . 62
K.2.2.3 RES* verification failure . 62
K.2.3 Threats related to security mode command procedure . 62
K.2.3.1 Bidding Down . 62
K.2.3.2 NAS integrity selection and use . 63
K.2.3.3 NAS NULL integrity protection . 63
K.2.3.4 NAS confidentiality protection . 63
K.2.4 Threats related to security in Intra-RAT mobility . 63
K.2.4.1 Bidding down on Xn-Handover . 63
K.2.4.2 NAS integrity protection algorithm selection in AMF change . 63
K.2.5 Threats related to release of non-emergency bearer . 64
K.2.6 Threats related to initial registration procedure . 64
K.2.6.1 Invalid or unacceptable UE security capabilities .
...