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ZTE RAN Solution
Security Target
LEGAL INFORMATION
Copyright © 2019 ZTE CORPORATION.
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All company, brand and product names are trade or service marks, or registered trade or service marks, of ZTE
CORPORATION or of their respective owners.
This document is provided “as is”, and all express, implied, or statutory warranties, representations or conditions
are disclaimed, including without limitation any implied warranty of merchantability, fitness for a particular
purpose, title or non-infringement. ZTE CORPORATION and its licensors shall not be liable for damages
resulting from the use of or reliance on the information contained herein.
ZTE CORPORATION or its licensors may have current or pending intellectual property rights or applications
covering the subject matter of this document. Except as expressly provided in any written license between ZTE
CORPORATION and its licensee, the user of this document shall not acquire any license to the subject matter
herein.
Users may visit ZTE technical support website http://ensupport.zte.com.cn to inquire related information.
The ultimate right to interpret this product resides in ZTE CORPORATION.
Revision History
Version Date Comment
0.1 Oct 23 2019 First version
0.2 Dec 16 2019 General revision
0.3 Jan 14 2020 General revision applying changes
0.4 Jan 22 2020 General revision applying changes
0.7 July 27 2020 Minor revision applying changes
0.9 August 6 2020 SPD and security objectives added.
0.10 August 10 2020 UME components changed
0.11 August 14 2020 Update UME components
0.12 August 17 2020 Fix SFR operations
0.13 August 19, 2020 Fix minor issues
0.14 August 21, 2020 Minor fixes and an application note added to
FTP_ITC.1/BBU-UE.
0.15 August 27, 2020 Change UME version and minor fix in SFR operations.
0.16 September 1, 2020 Accepted changes
0.17 September 29, 2020 Section 6.2 updated
0.18 October 10, 2020 FTA_MCS.1/BBU and TSS updated
0.19 October 22, 2020 FTA_MCS.1/BBU Basic limitation on multiple concurrent
sessions updated
0.20 December 17, 2020 Updated after evaluator’s feedback.
0.21 January 19, 2021 FAU_STG.4/BBU added to Security Functional
Requirements Rationale and the dependencies table.
0.22 February 4, 2021 Fixed versions of the acceptance procedure documents
[UG-BBU-ACP] and [UG-UME-ACP].
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Contents
1 ST Introduction..................................................................................................... 6
1.1 ST reference ....................................................................................................... 6
1.2 TOE reference .................................................................................................... 6
1.3 TOE Overview and usage................................................................................... 6
1.3.1 Major security features..................................................................................... 7
1.3.2 Non-TOE Hardware/Software/Firmware.......................................................... 8
1.4 TOE Description.................................................................................................. 8
1.4.1 Physical scope ................................................................................................. 8
1.4.2 Logical scope ................................................................................................. 10
2 Conformance Claims ......................................................................................... 11
3 Security Problem Definition.............................................................................. 13
3.1 Assets ............................................................................................................... 13
3.2 Threat agents.................................................................................................... 13
3.3 Threats.............................................................................................................. 13
3.4 Assumptions...................................................................................................... 14
4 Security Objectives............................................................................................ 15
4.1 Security objectives for the TOE ........................................................................ 15
4.2 Security objectives for the Operational Environment........................................ 15
5 Security Requirements...................................................................................... 17
5.1 Extended components definition....................................................................... 17
5.2 Definitions ......................................................................................................... 17
5.2.1 Subjects: ........................................................................................................ 17
5.2.2 Operations...................................................................................................... 17
5.2.3 Objects........................................................................................................... 17
5.2.4 Security attributes .......................................................................................... 18
5.2.5 BBU And AAU/RRU entity: ............................................................................ 19
5.2.6 External entities: ............................................................................................ 19
5.3 Security Functional Requirements.................................................................... 20
5.4 Security Assurance Requirements ................................................................... 31
5.5 Security Assurance Requirements Rationale ................................................... 32
6 TOE Summary Specification............................................................................. 33
7 Rationales........................................................................................................... 37
7.1 Security Objectives Rationale........................................................................... 37
7.2 Security Functional Requirements Rationale.................................................... 38
7.3 Dependencies ................................................................................................... 40
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1 ST Introduction
1.1 ST reference
Title ZTE RAN Solution Security Target
Version 0.22
Date February 04, 2021
Author ZTE
1.2 TOE reference
TOE Name ZTE RAN
TOE version V3.00.30.20P10
TOE Components baseband unit (BBU) ZXRAN V9200
remote RF unit (RRU) ZXRAN R9105
ZXSDR R8998
ZXSDR R8862
ZXSDR R8852
ZXRAN R8894
ZXRAN R8854
ZXRAN R9212
ZXRAN R9214
ZXRAN R9222
Active Antenna Unit
(AAU)
ZXRAN A9611
ZXRAN A9815
ZXRAN A9631
ZXRAN A9622
Unified Management Expert (UME), V16.20.30
Developer ZTE
1.3 TOE Overview and usage
The TOE is a New Generation Radio Access Network (NG-RAN) system solution
for NR (new radio) network plus an UME. The solution interfaces with User
Equipment (UE) and implements such functions as radio resource management,
data stream IP header compression and encryption, attach progress selection,
user plane data routing, data scheduling and transmission, and mobility
management. The UME is used to manage the system via web interface.
The TOE consists of three parts; a baseband unit (BBU), a remote RF unit (RRU)
or an active antenna unit (AAU) and a unified management expert (UME):
 BBU is the device processing the analog to digital conversion of the
signal;
 RRU is the remote radio unit transceiver;
 AAU incorporates a radio frequency processing module and antenna;
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 UME is a unified intelligent operation and maintenance system for RAN.
UME provides the intelligent operation and maintenance management of
network and the on-demand deployment and the gray-scale based upgrade of
system.
The TOE is connected by three networks:
 Core network: This is the internal network of the provider, and is
considered secure in this evaluation.
 A backhaul network: This is an external network and is considered
insecure in this evaluation.
 An IP Management network: This is the internal network of the provider
and is considered secure in this evaluation.
The TOE and these networks are shown in Figure 1.
Figure 1: The TOE in its environment
The RAN which is equivalent to gNodeB has the following general functionalities:
 Radio resource management: radio bearer control, radio admission control;
 Access mobility management;
 IP header compression and user data stream encapsulation;
 Paging message scheduling and transmission;
 Broadcast message scheduling and transmission;
1.3.1 Major security features
The major security features of the TOE are:
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 Secure management and usage of the TOE, to ensure that only properly
authorized staff can manage and/or use the TOE;
 Provides secure interaction between various parts of the TOE and between
the TOE and various machines in the environment, so that user data
and/or management commands cannot be read or modified in between;
 Provides logging and auditing of user actions.
1.3.2 Non-TOE Hardware/Software/Firmware
The additional systems required by the TOE are:
 L3 Switches providing filtering services to the UME Server and BBU part of
the TOE;
 Secure Gateway: The RAN connects to a secure gateway (SEG) using
IPSec. The SEG then connects to a secure network (Core) where
AMF/UPF/UME connects to;
 UME server: the UME application requires a platform to run consisting on
the physical hardware and firmware, the operating system.
 AMF function providing:
o Allocating paging message to RAN;
o Security control;
o Idle state mobility control;
o UPF bearer control;
o NAS signaling encryption and integrity protection.
 UPF function providing:
o Supporting UE's mobility switching user plane data;
o Downlink packet data buffer and paging support in NG-RAN idle
mode.
1.4 TOE Description
1.4.1 Physical scope
The TOE consists of the following:
BBU Name and version
Hardware V9200
Software NR: V3.00.30.20P10
RRU Name and version
Hardware R9105, R9212, R8998, R8894, R8854, R9222 or
R9214
R8862 or R8852
Software V3.00.30.20P10
AAU Name and version
Hardware A9611, A9815, A9631 or A9622
Software V3.00.30.20P10
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UME Name and version
Software UME Server version ElasticNet UME V16.20.30
SSH Server(Apache SSHD v2.1.0)
SFTP server(apache-sshd-core v2.2.0)
LDAP server(ApacheDS 2.0.0-M24)
The TOE hardware parts are delivered by courier, while software parts are either
installed in the hardware or installed by ZTE engineers. The following documents
are delivered by the ZTE engineers to the customer during the TOE installation:
Document Version Format
[UG-BBU-ACP] Acceptance procedure 0.4 PDF
[UG-BBU-CONF] RAN Configuration Management 1.3 PDF
[UG-BBU-HW-DES] ZXRAN V9200 Radio Access Network Product
Description
2.0 PDF
[UG-BBU-HW-INS] ZXRAN V9200 Radio Access Network Hardware
Installation
2.0 PDF
[UG-BBU-OPE] RAN Element Management 1.0 PDF
[UG-BBU-SW-INS] ZXRAN Base Station Commissioning Guide (Image
Burning)
1.2 PDF
[UG-UME-ACP] Acceptance procedure 0.3 PDF
[UG-UME-INS] UME Installation and Deployment Guide 1.3 PDF
[UG-UME-LE] Security Log Events 1.0 PDF
[UG-UME-MML] UME Command List 1.0 PDF
[UG-UME-OPE-LOG] ElasticNet UME Log Management Operation
Guide
R1.0 PDF
[UG-UME-OPE-OAOG] ElasticNet UME Open API Service Operation
Guide
R1.0 PDF
[UG-UME-OPE-SMOG] ElasticNet UME Security Management
Operation Guide
R1.0 PDF
[UG-UME-PRE] UME Software Integrity Protection Evidence description 1.0 PDF
[UG-UME-SPM] Security Parameter Manual 1.0 PDF
[UG-UME-UPG] UME Upgrade Guide 1.12 PDF
ZXRAN A9622E S35 5G Hardware Installation 1.0 PDF
ZXRAN A9631 S26 5G Active Antenna Unit Hardware Installation Guide 1.0 PDF
ZXRAN A9815 5G Active Antenna Unit Hardware Installation 1.0 PDF
ZXRAN A9611 S35 5G Active Antenna Unit Hardware Installation 1.0 PDF
ZXRAN R9105 S26 5G Remote Radio Unit Hardware Installation 1.0 PDF
ZXRAN R9105 S35 5G Remote Radio Unit Hardware Installation 1.0 PDF
ZXRAN R9212E Macro Radio Remote Unit Hardware Installation Guide 1.0 PDF
ZXRAN R9214E Macro Radio Remote Unit Hardware Installation 1.0 PDF
ZXRAN R9222 Macro Radio Remote Unit Hardware Installation Guide 1.0 PDF
ZXSDR R8862A Macro Remote Radio Unit Hardware Installation 1.0 PDF
ZXSDR R8998E S2600 TDD Multi-Path Remote Radio Unit Hardware 1.0 PDF
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Installation
ZXSDR R8998E S3700 TDD Multi-Path Remote Radio Unit Hardware
Installation
1.0 PDF
ZXSDR R8852E Macro Remote Radio Unit Hardware Installation 1.0 PDF
ZXSDR R8854E Macro Radio Remote Unit Hardware Installation 1.0 PDF
ZXSDR R8894E Macro Radio Remote Unit Hardware Installation 1.0 PDF
ZXSDR R8894E Macro Radio Remote Unit Hardware Installation 1.0 PDF
1.4.2 Logical scope
The architecture of the TOE’s system is described in Figure 1. The TOE provides
the following security functionalities:
 Users identification and authentication a is enforced so users must be
authenticated by password before using or managing the TOE. User
session are monitored and passwords are verified to enforce secure
authentication;
 Access control is strictly enforced to TOE users based on their role and the
access control policy;
 User management functionalities are provided to control the users and
their attributes (role, password, idle time, account lock, etc.);
 TOE communications provide identification of its end-points and are
protected against modification or disclosure. This protection includes the
communication between TOE parts (UME, BBU-SEG, BBU-BBU) and
communication between the TOE and external entities (BBU-UE);
 User activities on UME are recorded to provide full accountability of the
user actions, and the log trail is protected against unauthorized
modification. The TOE provides administrators with the log review
capabilities.
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2 Conformance Claims
This ST conforms to:
 CC, version 3.1R5, as defined by [CCp1], [CCp2], [CCp3] and [CEMe].
 CC Part 2 as CC Part 2 conformant
 CC Part 3 as CC Part 3 conformant
This ST conforms to no Protection Profile.
This ST conforms to EAL 3+ALC_FLR.2, and to no other packages.
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3 Security Problem Definition
This section describes the assets, thread agents and threads to the TOE.
3.1 Assets
A.USER_DATA User data from a user device that is transmitted by the
TOE.
A.TSF_DATA TSF data stored and managed by the UME and the BBU
and that is used to enforce the security mechanism, such
as the stored user passwords, the user attributes, or the
encryption keys for the trusted channels. This data shall
only be modified by users with A.ADMIN_ACCESS
A.ADMIN_ACCESS Administrative access to the UME and to the BBU.
A.TSF_ACTIVITY_LOGS User and administrator log records generated by the TSF.
3.2 Threat agents
TA.REMOTE A attacker with access to the backhaul Network that is
connected to the TOE and/or with access to the air
network between UE and RRU/AAU. This agent does not
have authorized access to the UME or the BBU.
TA.USER An attacker with authorised access to the UME or the
BBU, but without any administrative rights.
3.3 Threats
T.COMMUNICATION_CH TA.REMOTE may be able to disclose or modify
A.USER_DATA or A.TSF_DATA data while being
transmitted through unsecure networks.
T.UNAUTHENTICATED_USER TA.REMOTE may be able to bypass the user
authentication and to access the UME or the BBU and
perform administrative actions (A.ADMIN_ACCESS) on
the TOE and modify A.TSF_DATA .
T.UNAUTHORIZED_ADMIN TA.USER may be able to bypass the access control
policy of the UME or the BBU and perform administrative
actions (A.ADMIN_ACCESS) without administrator rights
and modify A.TSF_DATA.
T.UNDETECTED_ACTIVITY TA.REMOTE or TA.USER may be able to attempt or
perform abusive actions on the UME or the BBU without
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administrator awareness (A.TSF_ACTIVITY_LOGS).
3.4 Assumptions
A.TIME The environment will provide a reliable timestamp for the
TOE.
A.UME_TRUSTED_NETWORK The UME is deployed in a controlled environment; at the
operator's equipment room in a trusted network. The
UME is segregated from the core network and IP
management network so only authorized network traffic is
allowed.
A.PHYSICAL_PROTECTION BBU and UME server hardware equipment are placed in
a safe and controllable space. These equipment is
maintained and operated only by authorized personnel.
A.ADMINISTRATORS The personnel working as authorized administrators are
trustworthy and trained for the TOE administration.
A.UME_PLATFORM The underlying hardware, firmware, operating system an
d other non-TOE software of the UME works correctly.
A.UME_CLIENT The administrator uses a secure remote management
terminal for remote access to the TOE. The client is up to
date regarding security upgrades and cryptographic
support.
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4 Security Objectives
The security objectives describe how the threats described in the previous section
will be addressed. It is divided into:
 The Security Objectives for the TOE, describing what the TOE will do to
address the threats
 The Security Objectives for the Operational Environment, describing
what other entities must do to address the threats
A rationale that the combination of all of these security objectives indeed
addresses the threats may be found in section 7.1 of this Security Target.
4.1 Security objectives for the TOE
O.SECURE_COMUNICATION The TOE shall provide the means to establish the
following secure communication channels between:
1. The subscriber (UE) and the BBU;
2. A BBU and another BBU;
3. A BBU and the trusted gateway of the core
network;
4. The UME and the UME Client.
O.USER_AUTHENTICATION The TOE shall enforce the user authentication on all
user access to the BBU and UME.
O.ACCESS_CONTROL The TOE shall implement a flexible role-based
authorization framework. Each role allows a user to
perform certain actions, and the TOE shall ensure
that users can only perform actions when they have
a role that allows them to perform such action.
O.AUDITING The TOE shall enforce logging of user actions and
provide auditing capabilities to the administrator
role.
4.2 Security objectives for the Operational Environment
OE.TIME The TOE environment shall provide reliable time via
NTP service.
OE.UME_TRUSTED_NETWORK The network segment used by the UME shall be secure
and provide segregation from other networks via trusted
gateway. The secure gateway (SEG) shall be able to
provide secure communication with the BBU.
OE.PHYSICAL_PROTECTION BBU and UME server hardware equipment shall be
placed in a safe and controllable space. These
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equipment shall be maintained and operated only by
authorized personnel.
OE.ADMINISTRATORS The personnel working as authorized administrators
shall be trustworthy and thoroughly trained for the TOE
administration and will follow the TOE’s user guidance.
OE.UME_PLATFORM The underlying hardware, firmware, operating system
an d other non-TOE software of the UME shall work
correctly.
OE.UME_CLIENT The UME administrator shall use a secure remote
management terminal for remote access to the TOE.-
The client shall be up to date regarding security
upgrades and cryptographic support.
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5 Security Requirements
5.1 Extended components definition
There are no extended components defined.
5.2 Definitions
The following terms are used in the security requirements:
5.2.1 Subjects:
 S.UME-user: the users with access to the UME and that are responsible
for the TOE management and that are connected through the IP
Management network;
 S.BBU-user: the users with access to the BBU and that are responsible for
the BBU management and that are connected through the local network.
5.2.2 Operations
 OP.lockUnlockUser: to unlock or lock a user. A locked user is not able to
log-in to the UME or BBU;
 OP.lockUnlockRole: to lock or unlock a role. A locked role prevents users
that only have the locked role to operate the UME, excluding the following
functions:
o Change their password;
o Log out from UME;
o View UME version information;
o Set time zone and DST;
o Change view language.
 OP.enableDisableUser: to enable or disable a user account. A disabled
user account cannot login to the UME or BBU;
 OP.userManagement: to perform user management functions, which
include to add, remove users or modify user attributes from UME and
BBU;
 OP.logReview: to review the logs generated by the UME;
 OP.RuleManagement: to perform security rule management functions,
which include managements functions include add, remove or modify
security rule;
 OP.idleTimeout: to set the amount of time that a user can remain idle
before it is logged out from the UME or BBU.
5.2.3 Objects
 O.user: this object includes all information of the user account. The
specific fields can be seen in the following section as these are considered
security attributes;
 O.role: this object includes all information of the role object. The specific
fields can be seen in the following section as these are considered security
attributes;
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 O.rule: this object includes all information of the security rule. The specific
fields can be seen in the following section as these are considered security
attributes;
 O.setting: this object includes all information of the security common
settings. The specific fields can be seen in the following section as these
are considered security attributes.
5.2.4 Security attributes
 Rule
o Rule.passwordExpirationDate: is the expiration date of user
password if used;
o Rule.passwordHistoryNumber: the history number of the last
passwords. When set, the user cannot use the passwords in this
password history for when changing the password.
o Rule.allowedIPs: is the list of the allowed source IPs for the user
to log-in. If the log-in is requested from other IPs access is denied;
o Rule.allowedWorkSchedule: is the accepted time schedule for
the user to log-in. Outside this timeframe the user is not allowed
for UME ;
o Rule.authenticationAttempts: is the maximum authentication
attempts allowed for the user before locking its account.
o Rule.lockedPeriod: is the period of time that the user account will
remain locked;
 Setting
o Setting.idleTimeout: is the amount of time that the user can
remain idle before it is logged out from the UME or the BBU.
 User
o User.username: User unique identifier;
o User.password: the user password;
o User.passwordHistory: the user password change history;
o User.rolesList: is the list of roles of the user;
o User.rule: is the security rule of the user;
o User.isLocked: this indicates if the user account is locked or not.
Only not locked users are allowed to login;
o User.isEnable: this Indicated if the user is enabled and can be
used or not. Only enabled users are allowed to login;
 Roles
o Role.type(UME): it can be one of the following:
 Security Administrator: this role has the right to conduct
security data maintenance, but it has no business related
privileges;
 Administrator: this role has complete and unrestricted
access to system, except maintenance of the security
information;
 Maintenance: this role has complete access to system and
its managed network, except maintenance of the security
information and maintenance system;
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 Operator: this role has the right to view network
information and conduct normal maintenance, but it cannot
modify system sensitive information;
 Supervisor: this role has the right to view system
information.
o Role.type(BBU): it can be one of the following:
 Administrator - super root user, which is not restricted by
password expiration;
 Maintenance - other user, which cannot create or modify
user information and is restricted by password expiration;
 Ordinary – ordinary user with no read, write, or execute
permission for security management node data, and have
read-only permission for other nodes such as radio
common service, device, transport network, gNode
function models.
o Role.islocked: this indicates if the role is locked or not. When a
role is locked the users with that role cannot operate UME.
5.2.5 BBU And AAU/RRU entity:
The AAU/RRU and the BBU are connected through an optical fiber and
communicate through the standard CPRI protocol. The following figure shows the
CPRI packet format:
5.2.6 External entities:
 UE: user equipment used by the subscribers to connect to the BBUs using
the backhaul network.
 Other BBU: this is another BBU working in the TOE environment but
performing the same function as the TOE’s BBU.
 Secure gateway (SEG): is the gateway connecting the UME in the core
network to the BBUs.
The following notational conventions are used in the requirements. Operations are
indicated in bold, except refinements, which are indicated in bold italic. In general
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refinements were applied to clarify requirements and/or make them more readable.
Iterations were indicated by adding three letters to the component name.
5.3 Security Functional Requirements
The security functional requirements are for UME and BBU. Since AAU/RRU that
only enhances 3D beam forming for cubic coverage does not contain the security
function, this section does not describe the security function requirements of AAU
and RRU.
5.3.1 Security Functional Requirements for the UME
5.3.1.1 FIA_UID.2/UME User identification before any action
FIA_UID.2.1 The TSF shall require each S.UME-user user to be successfully
identified before allowing any other TSF-mediated actions on behalf of that user.
5.3.1.2 FIA_UAU.2/UME User authentication before any action
FIA_UAU.2.1 The TSF shall require each S.UME-user user to be successfully
authenticated before allowing any other TSF-mediated actions on behalf of that
user.
5.3.1.3 FIA_AFL.1/UME Authentication failure handling
FIA_AFL.1.1 The TSF shall detect when a security administrator configurable
positive integer within 3 and 20 (Rule.authenticationAttempts, default 3)
unsuccessful authentication attempts occur related to S.UME-user authentication.
FIA_AFL.1.2 When the defined number of unsuccessful authentication attempts
has been met, the TSF shall lock the S.UME-user account
 Until is unlocked by the Security administrator, or
 Until a security administrator configurable time (Rule.lockedPeriod)
have passed, if the account has not been set to permanent locking.
5.3.1.4 FIA_SOS.1/UME Verification of secrets
FIA_SOS.1.1 The TSF shall provide a mechanism to verify that User.password
meet:
 At least 8 characters including four types: number, upper case letter,
lower casee letter, other characters;
 Cannot be the same as the username, the username in reverse1
or a
common password dictionary word;
 The new password cannot be the same as one of the last
(Rule.passwordHistoryNumber) passwords set in
User.passwordHistory.
1
If the username is chang, “gnahc” is not allowed
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5.3.1.5 FTA_SSL.3/UME TSF-initiated termination
FTA_SSL.3.1 The TSF shall terminate an interactive session
 After a period of inactivity that equals the configured time
(Setting.idleTimeout);
 when one of the user roles in the user’s list (User.rolesList) is being
locked or being modified while the user is logged in.
5.3.1.6 FTA_MCS.1/UME Basic limitation on multiple concurrent sessions
FTA_MCS.1.1 The TSF shall restrict the maximum number of concurrent sessions
that belong to the same S.UME-user.
FTA_MCS.1.2 The TSF shall enforce, by default, a limit of 1 session per S.UME-
user.
5.3.1.7 FAU_GEN.1/UME Audit data generation
FAU_GEN.1.1 The UME shall be able to generate an audit record of the following
auditable events:
a) Start-up and shutdown of the audit functions;
b) All auditable events for the not specified level of audit; and
c) The following auditable events:
 S.UME-user authentication (security log);
 OP.lockUnlockUser (security log);
 OP.enableDisableUser (operation log);
 OP.userManagement (operation log);
 OP.ruleManagement (operation log);
 OP.idleTimeout (operation log).
FAU_GEN.1.2 The TSF shall record within each audit record at least the following
information:
a) Date and time of the event, type of event, subject identity (if applicable),
and the outcome (success or failure) of the event; and
b) For each audit event type, based on the auditable event definitions of the
functional components included in the PP/ST, none.
Application note: Start-up and shutdown of the audit functions is not explicitly
logged, however the logging functionality is enabled at start-up and cannot be
disabled.
5.3.1.8 FAU_SAR.1/UME Audit review
FAU_SAR.1.1 The TSF shall provide S.UME-user with Administrator or Security
Administrator in User.rolesList with the capability to read all log records from
the audit records.
FAU_SAR.1.2 The TSF shall provide the audit records in a manner suitable for the
user to interpret the information.
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5.3.1.9 FAU_STG.1/UME Protected audit trail storage
FAU_STG.1.1 The TSF shall protect the stored audit records in the audit trail from
unauthorised deletion.
FAU_STG.1.2 The TSF shall be able to prevent unauthorised modifications to the
stored audit records in the audit trail.
5.3.1.10 FAU_STG.4/UME Prevention of audit data loss
FAU_STG.4.1 The TSF shall overwrite the oldest stored audit records2
if the
audit trail is full.
Application note: Audit records can be exported to a backup server.
5.3.1.11 FTP_TRP.1/UME-Client Trusted path
FTP_TRP.1.1 The TSF shall provide a communication path between itself and
S.UME-user that is logically distinct from other communication paths and provides
assured identification of its end points and protection of the communicated data
from modification and disclosure.
FTP_TRP.1.2 The TSF shall permit S.UME-user to initiate communication via the
trusted path.
FTP_TRP.1.3 The TSF shall require the use of the trusted path for initial user
authentication and all UME management functions defined in
FMT_SMF.1/UME.
5.3.1.12 FIA_ATD.1/UME User attribute definition
FIA_ATD.1.1 The TSF shall maintain the following list of security attributes
belonging to individual S.UME-user:
 User.username;
 User.password;
 User.passwordHistory;
 User.rolesList;
 User.rule;
 User.isLocked;
 User.isEnable;
5.3.1.13 FMT_SMR.1/UME Security roles
FMT_SMR.1.1 The TSF shall maintain the roles:
o Security Administrator
o Administrator
o Maintenance
o Operator
2
The operation was completed to “take no other actions”, and this was subsequently refined away
to make the sentence more readable.
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o Supervisor
FMT_SMR.1.2 The TSF shall be able to associate users with roles.
5.3.1.14 FMT_SMF.1/UME Specification of Management Functions
FMT_SMF.1.1 The TSF shall be capable of performing the following management
functions:
Management function Related to SFR
OP.ruleManagement -> User.Rule.allowedIPs
Set wether a user(assigned the rule) can only login from
certain IP-addresses, and if so, which IP addresses.
FDP_ACF.1/UME
OP.idleTimeout -> Setting.idleTimeout
Set the time that users may remain logged in while inactive.
FTA_SSL.3/UME
OP.ruleManagement ->
User.Rule.allowedWorkSchedule
Set whether a user(assigned the rule) is only allowed to
work at certain times, and if so, at which times.
FDP_ACF.1/UME
OP.ruleManagement ->
User.Rule.authenticationAttempts
Set the number of allowed unsuccessful authentication
attempts
FIA_AFL.1/UME
OP.ruleManagement -> User.Rule.lockedPeriod
Set the time that an account(assigned the rule) remains
locked
FIA_AFL.1/UME
OP.lockUnlockUser -> User.isLocked
Unlock a user account
FIA_AFL.1/UME
OP.ruleManagement ->
User.Rule.passwordExpirationDate
Set whether a user(assigned the rule) password expires
after a certain time, and if so, after how long
FDP_ACF.1/UME
OP.ruleManagement -> Rule.passwordHistoryNumber
Set the length password history that it is maintained to
prevent the users from using the same password. E.g. if set
to 3, then the users cannot use the last 3 passwords
FIA_SOS.1/UME
OP.userManagement -> User.rolesList
Add or remove roles to/from users
FMT_SMR.1/UME
OP.userManagement
Create, edit and delete user accounts
FIA_ATD.1/UME
FIA_SOS.1/UME
OP.enableDisableUser -> User.isEnable
Disable/enable user accounts
FIA_ATD.1/UME
OP.lockUnlockRole
Lock/unlock roles
FTA_SSL.3/UME
OP.logReview
Log review
FAU_SAR.1/UME
5.3.1.15 FDP_ACC.2/UME Complete access control
FDP_ACC.2.1 The TSF shall enforce the Role-based Access Control Policy on
 Subjects:
o S.UME-user
 Objects:
o O.user;
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o O.role;
o O.rule;
o O.setting.
and all operations among subjects and objects covered by the SFP.
FDP_ACC.2.2 The TSF shall ensure that all operations between any subject
controlled by the TSF and any object controlled by the TSF are covered by an
access control SFP
5.3.1.16 FDP_ACF.1/UME Security attribute based access control
FDP_ACF.1.1 The TSF shall enforce the Role-based Access Control Policy to
objects based on the following:
 Subjects:
o S.UME-user, with security attributes:
 User.rolesList;
 User.rule;
 User.isLocked;
 User.isEnable;
 Objects:
o O.user;
o O.role.
o O.rule;
o O.setting.
FDP_ACF.1.2/ The TSF shall enforce the following rules to determine if an
operation among controlled subjects and controlled objects is allowed:
 S.UME-user is allowed to perform all operations defined in
FMT_SMF.1.1/UME, if and only if the user is authenticated and his
User.rolesList includes the value: Security Administrator;
o S.UME-user is allowed to perform OP.logReview, if the user is
authenticated and his User.rolesList includes a role that has log view
right.
FDP_ACF.1.3 The TSF shall explicitly authorise access of subjects to objects
based on the following additional rules: None.
FDP_ACF.1.4 The TSF shall explicitly deny access of subjects to objects based on
the following additional rules:
 S.UME-user is locked (User.isLocked is True);
 S.UME-user is not enabled (User.isEnable is False);
 S.UME-user has no role assigned (User.rolesList is empty);
 S.UME-user password has expired (current time >=
User.rule.passwordExpirationDate);
 S.UME-user source IP is not allowed (not included in
User.rule.allowedIPs);
 S.UME-user session has been terminated due to:
o Inactivity (Setting.idleTimeout);
o His role is being edited by a security administrator
(User.rolesList).
 The operation is performed outside the allowed time schedule of
S.UME-user (User.rule.allowedWorkSchedule);
 Role.type security administrator is locked.
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5.3.1.17 FMT_MSA.1/UME Management of security attributes
FMT_MSA.1.1 The TSF shall enforce the UME Access Control Policy to restrict
the ability to change_default and modify, delete the security attributes:
 Rule.passwordExpirationDate
 Rule.passwordHistoryNumber
 Rule.allowedIPs
 Rule.allowedWorkSchedule
 Rule.authenticationAttempts
 Rule.lockedPeriod
 Setting.idleTimeout
 User.username
 User.password
 User.passwordHistory
 User.rolesList
 User.rule
 User.isLocked
 User.isEnable
 Role.type
 Role.islocked
to Security Administrator.
5.3.1.18 FMT_MSA.3/UME Static attribute initialisation
FMT_MSA.3.1 The TSF shall enforce the UME Access Control Policy to provide
restrictive default values for security attributes that are used to enforce the SFP.
FMT_MSA.3.2 The TSF shall allow the Security Administrator to specify
alternative initial values to override the default values when an object or
information is created.
5.3.2 Security Functional Requirements for the BBU
5.3.2.1 FIA_UID.2/BBU User identification before any action
FIA_UID.2.1 The TSF shall require each S.BBU-user user to be successfully
identified before allowing any other TSF-mediated actions on behalf of that user.
5.3.2.2 FIA_UAU.2/BBU User authentication before any action
FIA_UAU.2.1 The TSF shall require each S.BBU-user user to be successfully
authenticated before allowing any other TSF-mediated actions on behalf of that
user.
5.3.2.3 FIA_SOS.1/BBU Verification of secrets
FIA_SOS.1.1 The TSF shall provide a mechanism to verify that User.password
meet:
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 The range of the password minimum length is 6~20, and the default
recommended value is 12. including four types: number, upper case
letter, lower case letter, other characters;
 The new password cannot be the same as one of the last
(Rule.passwordHistoryNumber) passwords set in
User.passwordHistory.
5.3.2.4 FIA_AFL.1/BBU Authentication failure handling
FIA_AFL.1.1 The TSF shall detect when an administrator configurable positive
integer (User.Rule.authenticationAttempts) within 1 and 6 (default 6),
unsuccessful authentication attempts occur related to S.BBU-user authentication.
FIA_AFL.1.2 When the defined number of unsuccessful authentication attempts
has been met, the TSF shall lock the S.BBU-user account
 Until is unlocked by the administrator, or
 Until an administrator configurable time (Rule.lockedPeriod) has
passed, if the account has not been set to permanent locking.
5.3.2.5 FTA_MCS.1/BBU Basic limitation on multiple concurrent sessions
FTA_MCS.1.1 The TSF shall Restricts the maximum number of
Concurrent sessions that belong to the same S.BBU-user.
FTA_MCS.1.2 The TSF shall enforce, by default, a limit of 5 sessions per user.
Application note: The maximum number of concurrent user session is 20.
5.3.2.6 FTA_SSL.3/BBU TSF-initiated termination
FTA_SSL.3.1 The TSF shall terminate an interactive session after a period of
inactivity that equals the configured time (Setting.idleTimeout).
5.3.2.7 FAU_GEN.1/BBU Audit data generation
FAU_GEN.1.1 The BBU shall be able to generate an audit record of the following
auditable events:
a) Start-up and shutdown of the audit functions;
b) All auditable events for the not specified level of audit; and
c) The following auditable events:
 S.BBU-user authentication (security log);
 OP.lockUnlockUser (security log);
 OP.userManagement (operation log);
 OP.idleTimeout (operation log).
FAU_GEN.1.2 The TSF shall record within each audit record at least the following
information:
a) Date and time of the event, type of event, subject identity (if applicable),
and the outcome (success or failure) of the event; and
b) For each audit event type, based on the auditable event definitions of the
functional components included in the PP/ST, none.
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Application note: Start-up and shutdown of the audit functions is not explicitly
logged, however the logging functionality is enabled at start-up and cannot be
disabled.
5.3.2.8 FAU_STG.1/BBU Protected audit trail storage
FAU_STG.1.1 The TSF shall protect the stored audit records in the audit trail from
unauthorised deletion.
FAU_STG.1.2 The TSF shall be able to prevent unauthorised modifications to the
stored audit records in the audit trail.
5.3.2.9 FAU_STG.4/BBU Prevention of audit data loss
FAU_STG.4.1 The TSF shall overwrite the oldest stored audit records3
if the
audit trail is full.
Application note: Audit records can be exported to a backup server.
5.3.2.10 FTP_ITC.1/BBU-SEG Inter-TSF trusted channel
FTP_ITC.1.1 The BBU shall provide a communication channel between itself and
SEG that is logically distinct from other communication channels and provides
assured identification of its end points and protection of the channel data from
modification or disclosure.
FTP_ITC.1.2 The BBU shall permit the BBU and the SEG to initiate
communication via the trusted channel.
FTP_ITC.1.3 The BBU shall initiate communication via the trusted channel for
transmission of user data.
5.3.2.11 FTP_ITC.1/BBU-BBU Inter-TSF trusted channel
FTP_ITC.1.1 The BBU shall provide a communication channel between itself and
another BBU that is logically distinct from other communication channels and
provides assured identification of its end points and protection of the channel data
from modification or disclosure.
FTP_ITC.1.2 The BBU shall permit the BBU and the other BBU to initiate
communication via the trusted channel.
FTP_ITC.1.3 The BBU shall initiate communication via the trusted channel for
transmission of user data.
5.3.2.12 FTP_ITC.1/BBU-UE Inter-TSF trusted channel
FTP_ITC.1.1 The TSF shall provide a communication channel between itself and
UE that is logically distinct from other communication channels and provides
3
The operation was completed to “take no other actions”, and this was subsequently refined away
to make the sentence more readable.
Security Target ZTE RAN Solution
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assured identification of its end points and protection of the channel data from
modification or disclosure.
FTP_ITC.1.2 The TSF shall permit the TSF and the UE to initiate communication
via the trusted channel.
FTP_ITC.1.3 The TSF shall initiate communication via the trusted channel for
transmission of user data.
Application note: This SFR is enforced by default by the BBU. However, the 3GPP
specification [TS33-501] requires that the BBU allows non-encrypted connections
from the UE.
5.3.2.13 FIA_ATD.1/BBU User attribute definition
FIA_ATD.1.1 The TSF shall maintain the following list of security attributes
belonging to individual S.BBU-user:
 User.username;
 User.password;
 User.rolesList;
 User.isLocked;
 User.isEnable;
 User.passwordHistory;
 User.rule.allowedIPs;
 User.rule.passwordHistoryNumber;
 User.rule.authenticationAttempts;
 User.Rule.lockedPeriod;
5.3.2.14 FMT_SMR.1/BBU Security role
FMT_SMR.1.1 The TSF shall maintain the roles:
o Administrator
o Maintenance
o Ordinary
FMT_SMR.1.2 The TSF shall be able to associate users with roles.
5.3.2.15 FMT_SMF.1/BBU Specification of Management Functions
FMT_SMF.1.1 The TSF shall be capable of performing the following management
functions:
Management function Related to SFR
OP.ruleManagement -> User.Rule.allowedIPs
Set wether a user(assigned the rule) can only login from
certain IP-addresses, and if so, which IP addresses.
FDP_ACF.1/BBU
OP.idleTimeout -> Setting.idleTimeout
Set the time that users may remain logged in while inactive.
FTA_SSL.3/BBU
OP.ruleManagement ->
User.Rule.passwordExpirationDate
Set whether a user(assigned the rule) password expires
after a certain time, and if so, after how long
FDP_ACF.1/BBU
OP.ruleManagement -> Rule.passwordHistoryNumber FIA_SOS.1/BBU
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Set the length password history that it is maintained to
prevent the users from using the same password. E.g. if set
to 3, then the users cannot use the last 3 passwords.
OP.ruleManagement ->
User.Rule.authenticationAttempts
Set the number of allowed unsuccessful authentication
attempts
FIA_AFL.1/BBU
OP.ruleManagement -> User.Rule.lockedPeriod
Set the time that an account(assigned the rule) remains
locked
FIA_AFL.1/BBU
OP.lockUnlockUser -> User.isLocked
Unlock a user account
FIA_AFL.1/BBU
OP.userManagement
Create, edit and delete user accounts
FIA_ATD.1/BBU
FIA_SOS.1/BBU
OP.enableDisableUser
Disable/enable user accounts
FIA_ATD.1/BBU
OP.userManagement -> User.rolesList
Add or remove roles to/from users
FMT_SMR.1/BBU
5.3.2.16 FDP_ACC.2/BBU Complete access control
FDP_ACC.2.1 The TSF shall enforce the BBU Access Control Policy on:
Subjects:
 S.BBU.
Objects:
 O.user;
 O.role;
 O.rule;
 O.Setting.
and all operations among subjects and objects covered by the SFP.
FDP_ACC.2.2 The TSF shall ensure that all operations between any subject
controlled by the TSF and any object controlled by the TSF are covered by an
access control SFP.
5.3.2.17 FDP_ACF.1/BBU Security attribute based access control
FDP_ACF.1.1 The TSF shall enforce the Role-based Access Control Policy to
objects based on the following:
 Subjects:
o S.BBU-user, with security attributes:
 User.rolesList;
 User.isLocked;
 User.isEnable;
 User.rule.passwordExpirationDate;
 Role.type;
 Objects:
o O.user;
o O.role.
FDP_ACF.1.2 The TSF shall enforce the following rules to determine if an
operation among controlled subjects and controlled objects is allowed:
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 S.BBU-user is allowed to perform all operations defined in
FMT_SMF.1.1/BBU if and only if the user is authenticated and his
User.rolesList includes the value: Administrator;
FDP_ACF.1.3 The TSF shall explicitly authorise access of subjects to objects
based on the following additional rules: None.
FDP_ACF.1.4 The TSF shall explicitly deny access of subjects to objects based on
the following additional rules:
 S.BBU-user is locked (User.isLocked is True);
 S.BBU-user is not enabled (User.isEnable is False)
 S.BBU-user has no role assigned (User.rolesList is empty);
 S.BBU-user session has been terminated due to inactivity
(Setting.idleTimeout);
 S.BBU-user source IP is not allowed (not included in
User.rule.allowedIPs);
 S.BBU-user password has expired (current time >=
User.rule.passwordExpirationDate);
 Role.type Administrator is locked.
5.3.2.18 FMT_MSA.1/BBU Management of security attributes
FMT_MSA.1.1 The TSF shall enforce the BBU Access Control Policy to restrict
the ability to change_default and modify the security attributes:
 Rule.passwordExpirationDate
 Rule.passwordHistoryNumber
 Rule.allowedIPs
 Rule.authenticationAttempts
 Rule.lockedPeriod
 Setting.idleTimeout
 User.username
 User.password
 User.rolesList
 User.rule
 User.isLocked
 User.isEnable
 Role.type
 Role.islocked
to Administrator.
5.3.2.19 FMT_MSA.3/BBU Static attribute initialisation
FMT_MSA.3.1 The TSF shall enforce the BBU Access Control Policy to provide
permissive default values for security attributes that are used to enforce the SFP.
FMT_MSA.3.2 The TSF shall allow the Administrator to specify alternative initial
values to override the default values when an object or information is created.
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5.4 Security Assurance Requirements
The assurance requirements are EAL3+ ALC_FLR.2 and have been summarized
in the following table:
Assurance Class
Assurance Components
Identifier Name
ADV: Development
ADV_ARC.1 Security architecture description
ADV_FSP.3
Functional specification with
complete summary
ADV_TDS.2 Architectural design
AGD: Guidance
documents
AGD_OPE.1 Operational user guidance
AGD_PRE.1 Preparative procedures
ALC: Life-cycle support
ALC_CMC.3 Authorisation controls
ALC_CMS.3
Implementation representation
CM coverage
ALC_DEL.1 Delivery procedures
ALC_FLR.2 Flaw reporting procedures
ALC_DVS.1
Identification of security
measures
ALC_LCD.1
Developer defined life-cycle
model
ASE: Security Target
evaluation
ASE_CCL.1 Conformance claims
ASE_ECD.1 Extended components definition
ASE_INT.1 ST introduction
ASE_OBJ.2 Security objectives
ASE_REQ.2 Derived security requirements
ASE_SPD.1 Security problem definition
ASE_TSS.1 TOE summary specification
ATE: Tests
ATE_COV.2 Analysis of coverage
ATE_DPT.1 Testing: basic design
ATE_FUN.1 Functional testing
ATE_IND.2 Independent testing - sample
AVA: Vulnerability
assessment
AVA_VAN.2 Vulnerability analysis
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5.5 Security Assurance Requirements Rationale
The Security Assurance Requirements for this Security Target are
EAL3+ALC_FLR.2. The reasons for this choice are that:
 EAL 3 is deemed to provide a good balance between assurance and
costs and is in line with ZTE customer requirements.
 ALC_FLR.2 provides assurance that ZTE has a clear and functioning
process of accepting security flaws from users and updating the TOE
when required. This is also in line with ZTE customer requirements.
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6 TOE Summary Specification
This chapter describes how the TOE implements the security functional
requirements defined in chapter 5. The description covers both UME and BBU
SFRs unless explicitly stated.
6.1 User identification and authentication
The TOE users are required to identify and authenticate themselves before they
can perform any action using the TOE. User authentication is based on the
username and password provided by the users and has a limited number of
attempts before the user account is locked. Users can be unlocked by the security
administrator in the UME and by the administrator in the BBU. Users can also wait
to be automatically unlocked after a period of time that is configurable by the
security administrator in the UME and by the administrator in the BBU.
The TOE maintains user information in order to enforce authentication and access
control. The following information is maintained for each user:
 User name and password;
 Password history;
 List of user roles;
 User rules, including expiration date, the length of password history, allowed IPs,
allowed authentication time, number of authentication attempts and locked
period;
 Locked and enabled status indicators.
User concurrent sessions are limited to a maximum 1 for each user in the UME,
and 5 for each user of the BBU by default (with 20 as maximum configurable
value). Furthermore, the sessions are automatically terminated after period of
inactivity that is configurable by the security administrator in the UME and by the
administrator in the BBU. A user session is also automatically terminated in the
UME when the security administrator is editing the user roles.
User authentication can be restricted based on the user’s source IP. The
administrator can set an allowed IP (or set of IPs) so the user can only be
successfully authenticated by connecting from the allowed IP. The UME security
administrator can also restrict the time when a user can be authenticated in the
UME by setting an allowed time period on the UME configuration.
User passwords have to meet certain rules to ensure that the passwords cannot be
easily guessed or broken by brute force:
 (Only in the UME)At least 8 characters including four types: number, upper
case letter, lower case letter, other characters;
 (Only in the BBU )The range of the password minimum length is 6~20, and
the default recommended value is 12. including four types: number, upper
case letter, lower case letter, other characters;
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 (Only in the UME) Cannot be the same as the username, the username in
reverse or a common password dictionary word;
 The new password cannot be the same as one of the last
(Rule.passwordHistoryNumber) passwords set in User.passwordHistory.
Passwords that do not meet these rules are rejected by the TOE.
FIA_UID.2, FIA_UAU.2, FIA_AFL.1, FIA_ATD.1, FTA_MCS.1, FIA_SOS.1 and
FTA_SSL.3.
6.2 Access Control
The TOE enforces access control on users based on user roles. Each user role
has an allowed set of allowed actions (including various management actions). A
user can have more than one role, so the user access is the combination of all his
roles.
The following table identify the allowed action for each role in the UME:
Role Allowed actions
Security Administrator Security management operations (as defined in
FMT_SMF.1/UME)
All user’s log review.
Administrator All(include all user’s log review) operations except
security management operations.
Maintenance All (include self log review) except security
management operations and system management
operations.
Operator Normal maintenance operations (include self log
review) except security management operations.
Supervisor View operations (include self log review) except security
management operations.
The following table identify the allowed action for each role/group in the BBU:
Role/Group Allowed actions
Administrator Security management operations (as defined in
FMT_SMF.1/BBU)
Maintenance Read-only permission for security management node
data, and read, write, and execute permissions for
other node data
Ordinary Have no read, write, or execute permission for
security management node data, and have read-only
permission for other nodes
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Access control also verifies that user information is correct, such as that the user is
enabled and not locked, user is not idle, user’s IP is allowed, user's password is
not expired and user’s role is not locked. The access control on the UME also
checks the user's allowed time interval and if the user’s role is being edited by the
security administrator.
FMT_SMR.1, FDP_ACC.2, FDP_ACF.1, FMT_SMF.1, FMT_MSA.1 and
FMT_MSA.3
6.3 Audit
The TOE generates audit logs to record the following events:
 User authentication;
 Locking or unlocking a user account;
 Enabling or disabling a user account (only UME);
 Add, remove or modify a user account;
 Add, remove or modify a role (only UME);
 Add, remove or modify a user’s rule (only UME);
 When a user session is terminated by timeout;
The log records include date and time of event, subject identity (if applicable), and
the outcome (success or failure) of the event.
The TOE provides the capability to review the logs to the security administrator of
the UME.
The audit store is protected against manipulation. Log records cannot be edited
and can only be deleted by the administrator of the UME and by the administrator
of the BBU if the records are 30 days old or older.
The log records overwrite themselves when the log trail is full in the UME.
Nonetheless, the records can be automatically sent to a remote server set on the
UME’s management network.
FAU_GEN.1, FAU_SAR.1, FAU_STG.1 and FAU_STG.4
6.4 Secure communication
The TOE provides secure interaction between its various parts and between itself
and various machines in the environment, so that user data and/or management
commands cannot be read or modified in between.
Communication between the UME and the UME Client is protected by HTTPS.
The connection between the BBU and SEG is protected by IPSEC.
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The connection between the BBU and another BBU is protected by IPSEC.
The connection between the TOE and UE is protected by Encryption Algorithm.
Table security algorithms in different channels
Channel Security Technology Algorithms Key Length
UME-UME Client HTTPS ECDHE-RSA-AES256-GCM-SHA384;
DHE-RSA-AES256-GCM-SHA384;
ECDHE-RSA-AES128-GCM-SHA256;
DHE-RSA-AES128-GCM-SHA256.
BBU-SEG&BBU-BBU IPSEC aes128cbc,
aes192cbc,
aes256-cbc,
3descbc,
Aes:128,192,256
3des:192
TOE-UE Radio Security NULL,Snow3G,AES,ZUC 128bits
FTP_ITC.1 and FTP_TRP.1
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7 Rationales
7.1 Security Objectives Rationale
Assumptions/Threats Objectives
T.COMMUNICATION_CH This thread is directly covered by
O.SECURE_COMUNICATION as it enforce to use
secure communication channels on all communications
between:
1. The subscriber (UE) and the BBU;
2. A BBU and another BBU;
3. A BBU and the trusted gateway of the core network;
4. The UME and the UME Client.
T.UNAUTHENTICATED_USER This thread is directly covered by
O.USER_AUTHENTICATION as it enforces user
authentication on both BBU and UME components.
T.UNAUTHORIZED_ADMIN This thread is directly covered by
O.USER_AUTHENTICATION and
O.ACCESS_CONTROL as these enforce user
authentication and authorization based on the user’s
role.
T.UNDETECTED_ACTIVITY This thread is directly covered by
O.USER_AUTHENTICATION and O.AUDITING as
these enforce user authentication and logging of user
actions on the BBU and UME.
A.TIME This assumption is upheld by OE.TIME, which directly
covers the assumption.
A.UME_TRUSTED_NETWORK This assumption is upheld by
OE.UME_TRUSTED_NETWORK, which directly
covers the assumption.
A.PHYSICAL_PROTECTION This assumption is upheld by
OE.PHYSICAL_PROTECTION, which directly covers
the assumption.
A.ADMINISTRATORS This assumption is upheld by OE.ADMINISTRATORS,
which directly covers the assumption.
A.UME_PLATFORM This assumption is upheld by OE.UME_PLATFORM,
which directly covers the assumption.
A.UME_CLIENT This assumption is upheld by OE.UME_CLIENT, which
directly covers the assumption.
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7.2 Security Functional Requirements Rationale
Security objectives SFRs addressing the security objectives
O.SECURE_COMUNICATION This objective is met by:
 FTP_TRP.1/UME-Client for the secure
communication between the UME and the client;
 FTP_ITC.1/BBU-SEG for the secure
communication between the BBU and the secure
gateway;
 FTP_ITC.1/BBU-BBU for the secure
communication between the BBU and another
BBU;
 FTP_ITC.1/BBU-UE for the secure
communication between the BBU and the UE.
O.USER_AUTHENTICATION This objective is met by:
 User identification and authentication before any
action (FIA_UID.2/UME, FIA_UID.2/BBU,
FIA_UAU.2/UME and FIA_UAU.2/BBU);
 Limited user authentication attempts
(FIA_AFL.1/UME and FIA_AFL.1/BBU);
 Complex user password (FIA_SOS.1/UME and
FIA_SOS.1/BBU);
 Limitation of user session (FTA_SSL.3/UME,
FTA_SSL.3/BBU, FTA_MCS.1/UME and
FTA_MCS.1/BBU);
 Supporting user configuration (FMT_SMF.1/UME
and FMT_SMF.1/BBU).
O.ACCESS_CONTROL This objective is met by:
 User roles and attributes implementation
(FIA_ATD.1/UME, FIA_ATD.1/BBU,
FMT_SMR.1/UME and FMT_SMR.1/UME);
 Enforcing access control based on user roles and
attributes (FDP_ACC.2/UME, FDP_ACC.2/BBU,
FDP_ACF.1/UME, FDP_ACF.1/BBU,
FMT_MSA.1/UME, FMT_MSA.1/BBU,
FMT_MSA.3/UME and FMT_MSA.3/BBU);
 Supporting access control configuration
(FMT_SMF.1/UME and FMT_SMF.1/BBU).
O.AUDITING This objective is met by:
 Audit data generation (FAU_GEN.1/UME and
FAU_GEN.1/BBU);
 Audit data protection (FAU_STG.1/UME,
FAU_STG.1/BBU, FAU_STG.4/UME,
FAU_STG.4/BBU);
 Supporting audit data review (FAU_SAR.1/UME,
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Security objectives SFRs addressing the security objectives
FMT_SMF.1/UME and FMT_SMF.1/BBU).
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7.3 Dependencies
SFR Dependency Coverage
FIA_UID.2/UME None. None.
FIA_UAU.2/UME FIA_UID.1 FIA_UID.2/UME
FIA_AFL.1/UME FIA_UAU.1 FIA_UAU.1/UME
FIA_SOS.1/UME None. None.
FTA_SSL.3/UME None. None.
FTA_MCS.1/UME FIA_UID.1 FIA_UID.2/UME
FAU_GEN.1/UME FPT_STM.1 N/A See below
FAU_SAR.1/UME FAU_GEN.1 FAU_GEN.1/UME
FAU_STG.1/UME FAU_GEN.1 FAU_GEN.1/UME
FAU_STG.4/UME FAU_GEN.1 FAU_GEN.1/UME
FTP_TRP.1/UME-Client None. None.
FIA_ATD.1/UME None. None.
FMT_SMF.1/UME None. None.
FMT_SMR.1/UME FIA_UID.1 FIA_UID.2/UME
FDP_ACC.2/UME FDP_ACF.1 FDP_ACF.1/UME
FDP_ACF.1/UME FDP_ACC.1
FMT_MSA.3
FDP_ACC.1/UME
FMT_MSA.3/UME
FMT_MSA.1/UME FDP_ACC.1
FMT_SMR.1
FMT_SMF.1
FDP_ACC.2/UME
FMT_SMR.1/UME
FMT_SMF.1/UME
FMT_MSA.3/UME FMT_MSA.1
FMT_SMR.1
FMT_MSA.1/UME
FMT_SMR.1/UME
FIA_UID.2/BBU FIA_UID.1 FIA_UID.2/BBU
FIA_UAU.2/BBU FIA_UAU.1 FIA_UAU.1/BBU
FIA_SOS.1/BBU None. None.
FIA_AFL.1/BBU FIA_UAU.1 FIA_UAU.1/BBU
FTA_MCS.1/BBU FIA_UID.1 FIA_UID.2/BBU
FTA_SSL.3/BBU None. None.
FAU_GEN.1/BBU FPT_STM.1 N/A See below
FAU_STG.1/BBU FAU_GEN.1 FAU_GEN.1/BBU
FAU_STG.4/BBU FAU_GEN.1 FAU_GEN.1/BBU
FTP_ITC.1/BBU-SEG None. None.
FTP_ITC.1/BBU-BBU None. None.
FTP_ITC.1/BBU-UE None. None.
FIA_ATD.1/BBU None. None.
FMT_SMF.1/BBU None. None.
FMT_SMR.1/BBU FIA_UID.1 FIA_UID.2/BBU
FDP_ACC.2/BBU FDP_ACF.1 FDP_ACF.1/BBU
FDP_ACF.1/BBU FDP_ACC.1
FMT_MSA.3
FDP_ACC.1/BBU
FMT_MSA.3/BBU
FMT_MSA.1/BBU FDP_ACC.1 FDP_ACC.2/BBU
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FMT_SMR.1
FMT_SMF.1
FMT_SMR.1/BBU
FMT_SMF.1/BBU
FMT_MSA.3/BBU FMT_MSA.1
FMT_SMR.1
FMT_MSA.1/BBU
FMT_SMR.1/BBU
FPT_STM.1 cannot be implemented by the TOE because it does not have the capability to
generate reliable time stamps, therefore the time information is provided by a NTP server in the
TOE network (OE.TIME).
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A Abbreviations
AC Alternating Current
BBU baseband unit
BPL Baseband Processing module
CC Control and Clock module
DC Direct Current
EMS Element Management System
EPS Evolved Packet System
eNode B Evolved Node B
UME Unified Management Expert
gNode B generation Node B
NG-RAN NewGeneration -Radio Access Network
FA Fan Array Module
IP Internet Protocol
IPSEC Internet Protocol Secure
NR New Generation
LED Light Emitting Diode
LTE Long Term Evolution
L3 Layer 3
MME Mobility Management Entity
MAC Media Access Control
NAS Non-Access Stratum
NTP Network Time Protocol
PDCP Packet Data Convergence Protocol
PHY Physical Layer
PM Power Module
RF Radio Frequency
RLC Radio Link Control
RRU Remote Radio Unit
SA Site alarm Board
SE Site alarm Extension Board
S-GW Serving Gateway
AMF Access and Mobility Management Function
UPF User Port Function
SEG Security gateway
UE User Equipment
UMTS Universal Mobile Telecommunications System
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B References
[CCp1] Common Criteria for Information Technology Security Evaluation
Part 1: Introduction and general model, version 3.1 Revision 5,
April 2017.
[CCp2] Common Criteria for Information Technology Security Evaluation
Part 2: Security functional components, version 3.1 Revision 5,
April 2017.
[CCp3] Common Criteria for Information Technology Security Evaluation
Part 3: Security assurance components, version 3.1 Revision 5,
April 2017.
[CEMe] Common Methodology for Information Technology Security
Evaluation Evaluation methodology, version 3.1 Revision 5, April
2017.
[TS33-501] 3GPP TS33.501 Security architecture and procedures for 5G
system