ETSI TR 133 926 V15.2.0 (2019-10)

LTE; Security Assurance Specification (SCAS) threats and critical assets in 3GPP network product classes (3GPP TR 33.926 version 15.2.0 Release 15)

RTR/TSGS-0333926vf20

General Information

• Status: Published
• Publication Date: 08-Oct-2019
• Technical Committee: 3GPP SA 3 - Security
• Current Stage: 12 - Completion
• Completion Date: 09-Oct-2019

Standards Content (Sample)

ETSI TR 133 926 V15.2.0 (2019-10)






TECHNICAL REPORT
LTE;
Security Assurance Specification (SCAS) threats and
critical assets in 3GPP network product classes
(3GPP TR 33.926 version 15.2.0 Release 15)

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3GPP TR 33.926 version 15.2.0 Release 15 1 ETSI TR 133 926 V15.2.0 (2019-10)



Reference
RTR/TSGS-0333926vf20
Keywords
LTE,SECURITY
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3GPP TR 33.926 version 15.2.0 Release 15 2 ETSI TR 133 926 V15.2.0 (2019-10)
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3GPP TR 33.926 version 15.2.0 Release 15 3 ETSI TR 133 926 V15.2.0 (2019-10)
Contents
Intellectual Property Rights . 2
Legal Notice . 2
Modal verbs terminology . 2
Foreword . 6
1 Scope . 7
2 References . 7
3 Definitions and abbreviations . 7
3.1 Definitions . 7
3.2 Abbreviations . 7
4 Generic Network Product (GNP) class description . 8
4.1 Overview . 8
4.2 Minimum set of functions defining the GNP class . 9
4.3 Generic network product model . 9
4.3.1 Generic network product model overview . 9
4.3.2 Functions defined by 3GPP . 9
4.3.3 Other functions . 9
4.3.4 Operating System (OS) . 9
4.3.5 Hardware . 9
4.3.6 Interfaces. 10
4.4 Scope of the present document . 10
4.4.1 Introduction. 10
4.4.2 Scope regarding GNP functions defined by 3GPP . 11
4.4.3 Scope regarding other functions . 11
4.4.4 Scope regarding Operating System (OS) . 11
4.4.5 Scope regarding hardware . 11
4.4.6 Scope regarding interfaces . 11
5 Generic Assets and Threats . 11
5.1 Introduction . 11
5.2 Generic critical assets . 11
5.3 Generic threats . 12
5.3.0 Generic threats format . 12
5.3.1 Introduction. 12
5.3.2 Threats relating to 3GPP-defined interfaces . 13
5.3.3 Spoofing identity . 13
5.3.3.1 Default Accounts . 13
5.3.3.2 Weak Password Policies . 13
5.3.3.3 Password peek . 14
5.3.3.4 Direct Root Access . 14
5.3.3.5 IP Spoofing . 14
5.3.3.6 Malware . 14
5.3.3.7 Eavesdropping . 14
5.3.4 Tampering . 15
5.3.4.1 Software Tampering . 15
5.3.4.2 Ownership File Misuse . 15
5.3.4.3 External Device Boot . 15
5.3.4.4 Log Tampering . 15
5.3.4.5 OAM Traffic Tampering . 15
5.3.4.6 File Write Permissions Abuse . 16
5.3.4.7 User Session Tampering . 16
5.3.5 Repudiation . 16
5.3.5.1 Lack of User Activity Trace . 16
5.3.6 Information disclosure . 16
5.3.6.1 Poor key generation. 16
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3GPP TR 33.926 version 15.2.0 Release 15 4 ETSI TR 133 926 V15.2.0 (2019-10)
5.3.6.2 Poor key management . 17
5.3.6.3 Weak cryptographic algorithms . 17
5.3.6.4 Insecure Data Storage . 17
5.3.6.5 System Fingerprinting . 17
5.3.6.6 Malware . 17
5.3.6.7 Personal Identification Information Violation. 18
5.3.6.8 Insecure Default Configuration . 18
5.3.6.9 File/Directory Read Permissions Misuse . 18
5.3.6.10 Insecure Network Services . 18
5.3.6.11 Unnecessary Services . 18
5.3.6.12 Log Disclosure . 19
5.3.6.13 Unnecessary Applications . 19
5.3.6.14 Eavesdropping . 19
5.3.6.15 Security threat caused by lack of GNP traffic isolation . 19
5.3.7 Denial of service . 20
5.3.7.1 Compromised/Misbehaving User Equipments . 20
5.3.7.2 Implementation Flaw . 20
5.3.7.3 Insecure Network Services . 20
5.3.7.4 Human Error . 20
5.3.8 Elevation of privilege. 21
5.3.8.1 Misuse by authorized users . 21
5.3.8.2 Over-Privileged Processes/Services . 21
5.3.8.3 Folder Write Permission Abuse . 21
5.3.8.4 Root-Owned File Write Permission Abuse . 21
5.3.8.5 High-Privileged Files . 21
5.3.8.6 Insecure Network Services . 22
5.3.8.7 Elevation of Privilege via Unnecessary Network Services . 22
Annex A:  Aspects specific to the network product class MME . 23
A.1 Network product class description for the MME . 23
A.1.1 Introduction . 23
A.1.2 Minimum set of functions defining the MME network product class . 23
A.2 Assets and threats specific to the MME . 23
A.2.1 Critical assets . 23
A.2.2 Threats related to AKA procedures . 24
A.2.2.1 Access to 2G . 24
A.2.2.2 Resynchronization . 24
A.2.2.3 Failed Integrity check of Attach message . 24
A.2.2.4 Forwarding EPS authentication data to SGSN . 24
A.2.2.5 Forwarding unused EPS authentication data between different security domains . 24
A.2.3 Threats related to security mode command procedure . 25
A.2.3.1 Bidding Down . 25
A.2.3.2 NAS integrity selection and use . 25
A.2.3.3 NAS NULL integrity protection . 25
A.2.3.4 NAS confidentiality protection . 25
A.2.4 Threats related to security in Intra-RAT mobility . 25
A.2.4.1 Bidding down on X2-Handover . 25
A.2.4.2 NAS integrity protection algorithm selection in MME change . 26
A.2.5 Threats related to security in Inter-RAT mobility . 26
A.2.5.1 2G SIM access via idle mode mobility . 26
A.2.5.2 2G SIM access via handover. 26
A.2.5. 3 2G SIM access via SRVCC . 26
A.2.6 Threats related to release of non-emergency bearer . 26
Annex B:  Aspects specific to the network product class PGW . 28
B.1 Network product class description for the PGW . 28
B.1.1 Introduction . 28
B.1.2 Minimum set of functions defining the PGW network product class . 28
B.2 Assets and threats specific to the PGW . 28
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B.2.1 Critical assets . 28
B.2.2 Threats related to IP Address Allocation . 29
B.2.2.1 IP Address Reallocation Continuously. 29
B.2.3 Packet Forwarding . 29
B.2.3.1 Sending unauthorized packets to other UEs . 29
B.2.4 Emergency PDN Connection . 29
B.2.4.1 Inactive Emergency PDN Connection Release . 29
B.2.5 Threats related to charging relevant data . 29
B.2.5.1 Failure to assign unique TEID or Charging ID for a session . 29
Annex C:  Aspects specific to the network product class eNB . 30
C.1 Network product class description for the eNB . 30
C.1.1 Introduction. 30
C.1.2 Minimum set of functions defining the eNB network product class . 30
C.2 Assets and threats specific to the eNB . 30
C.2.1 Critical assets . 30
C.2.2 Threats related to Control plane and User plane . 31
C.2.2.1 Control plane data confidentiality protection . 31
C.2.2.2 Control plane data integrity protection . 31
C.2.2.3 User plane data ciphering and deciphering at eNB . 31
C.2.2.4 User plane data integrity protection . 31
Annex D: Change history . 32
History . 33

ETSI

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3GPP TR 33.926 version 15.2.0 Release 15 6 ETSI TR 133 926 V15.2.0 (2019-10)
Foreword
rd
This Technical Report has been produced by the 3 Generation Partnership Project (3GPP).
The contents of the present document are subject to continuing work within the TSG and may change following formal
TSG approval. Should the TSG modify the contents of the present document, it will be re-released by the TSG with an
identifying change of release date and an increase in version number as follows:
Version x.y.z
where:
x the first digit:
1 presented to TSG for information;
2 presented to TSG for approval;
3 or greater indicates TSG approved document under change control.
Y the second digit is incremented for all changes of substance, i.e. technical enhancements, corrections, updates, etc.
z the third digit is incremented when editorial only changes have been incorporated in the document.
ETSI

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3GPP TR 33.926 version 15.2.0 Release 15 7 ETSI TR 133 926 V15.2.0 (2019-10)
1 Scope
The present document captures the network product class descriptions, threats and critical assets that have been
identified in the course of the work on 3GPP security assurance specifications. The main body of the present document
contains generic aspects that are believed to apply to more than one network product class, while Annexes cover the
aspects specific to one network product class.
2 References
The following documents contain provisions which, through reference in this text, constitute provisions of the present
document.
- References are either specific (identified by date of publication, edition number, version number, etc.) or
non-specific.
- For a specific reference, subsequent revisions do not apply.
- For a non-specific reference, the latest version applies. In the case of a reference to a 3GPP document (including
a GSM document), a non-specific reference implicitly refers to the latest version of that document in the same
Release as the present document.
[1] 3GPP TR 21.905: "Vocabulary for 3GPP Specifications".
[2] 3GPP TR 33.916: "Security Assurance Methodology for 3GPP network products classes".
[3] 3GPP TS 23.401: "General Packet Radio Service (GPRS) enhancements for Evolved Universal
Terrestrial Radio Access Network (E-UTRAN) access".
[4] 3GPP TR 33.821: "Rationale and track of security decisions in Long Term Evolution (LTE)
RAN/3GPP System Architecture Evolution (SAE)".
[5] 3GPP TS 33.116: "Security Assurance Specification for MME network product class".
[6] 3GPP TS 33.250: "Security assurance specification for the PGW network product class".
3 Definitions and abbreviations
3.1 Definitions
For the purposes of the present document, the terms and definitions given in 3GPP TR 21.905 [1] and the following
apply. A term defined in the present document takes precedence over the definition of the same term, if any, in 3GPP
TR 21.905 [1].
GNP Class (Generic Network Product Class): generic network product class is a class of network products that all
implement a common set of 3GPP-defined functionalities for that particular network product
3.2 Abbreviations
For the purposes of the present document, the abbreviations given in 3GPP TR 21.905 [1] and the following apply.
An abbreviation defined in the present document takes precedence over the definition of the same abbreviation, if any,
in 3GPP TR 21.905 [1].
GNP Generic Network Product
SCAS Security Assurance Specification
SECAM Security Assurance Methodology
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3GPP TR 33.926 version 15.2.0 Release 15 8 ETSI TR 133 926 V15.2.0 (2019-10)
4 Generic Network Product (GNP) class description
4.1 Overview
A 3GPP generic network product class defines a set of functions that are implemented on that product, which includes,
but not limited to minimum set of common 3GPP functions for that product covered in 3GPP specifications, other
functions not covered by 3GPP specifications, as well as interfaces to access that product. A generic network product
also includes hardware, software, and OS components that the product is implem
...