ISO/IEC TR 3445:2022

TECHNICAL ISO/IEC TR
REPORT 3445
First edition
2022-03
Information technology — Cloud
computing — Audit of cloud services
Reference number
© ISO/IEC 2022
© ISO/IEC 2022
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Contents Page
Foreword .v
Introduction . vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
3.1 Terms related to the use of audit and assessment . 1
3.2 Terms related to cloud service audit . 3
4 Abbreviated terms . 5
5 Overview of cloud computing and the activities of a cloud auditor .5
5.1 Overview of cloud computing. 5
5.1.1 General . 5
5.1.2 Cloud computing roles, sub-roles and activities . 6
5.2 Overview of the activities of a cloud auditor . 7
5.2.1 Cloud auditor . 7
5.2.2 Responsibilities of a cloud auditor . 8
5.2.3 Cloud auditor’s cloud computing activities . 9
5.2.4 Relationship of the cloud auditor to CSPs, CSCs, and other CSNs . 10
6 Overview of the audit of cloud services .10
6.1 General . 10
6.2 Objectives of an audit of cloud service . 11
6.2.1 General . 11
6.2.2 Audit objectives . 11
6.2.3 Audit boundaries .13
6.2.4 Relationship of an audit and the organization .13
6.3 Types of cloud audit . .15
6.3.1 Overview . 15
6.3.2 Internal audit .15
6.3.3 External audit . 16
6.3.4 Exemplary tests and audits . 17
6.3.5 Relationship between audit and assessment for cloud computing . 19
6.3.6 Relationships among audit processes and reports . 19
6.3.7 Conformity Assessment – Objectives and expectations . 24
6.4 Cloud audit and trust . 24
7 Audit specifications and challenges .25
7.1 Overview . 25
7.2 Establishing audit scope .25
7.3 Audit risk assessment . .25
7.3.1 General . 25
7.3.2 Risk assessment of cloud computing systems and legacy or non-cloud
computing system .26
7.4 Security controls assessment .26
7.5 Required laws, regulations, and government requirements . 27
7.6 Policies .28
7.6.1 General .28
7.6.2 Geolocation data .28
7.7 Cloud service agreement (CSA) .28
7.8 Cloud capabilities types, cloud service categories and key characteristics .29
7.9 Cross-cutting aspects . 31
7.10 Emerging technologies and cloud native . 31
7.11 Define metrics and security parameters . 32
7.12 Determining matrix . 33
7.13 Assessment of cloud governance . 33
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7.14 Challenges of conducting an audit of cloud services . 33
7.14.1 General . 33
7.14.2 Third party auditability .33
7.14.3 Change management . 33
7.14.4 Patch management .34
7.14.5 Multi-tenant environment.34
7.14.6 Auditability and assurance .34
7.14.7 Availability requirement .34
8 Approaches to conducting audits .35
8.1 Typical Scenarios . 35
8.2 Cloud audit – opportunities and meeting objectives . 35
8.2.1 General . 35
8.2.2 Stakeholders and related activities on cloud audit .36
8.3 Processes – identify, analyse, evaluate . 36
8.4 Data flow – lifecycle - confidentiality, integrity, availability . 37
8.5 Automation of cloud service audits and assessments . 37
Annex A (informative) Sample list of standards and frameworks applicable to audit of
cloud services .39
Annex B (informative) Compilation of frameworks, schemes, and auditing programs for
certification, attestation and authorization which are relevant to cloud security . 44
Bibliography .49
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Foreword
ISO (the International Organization for Standardization) and IEC (the International Electrotechnical
Commission) form the specialized system for worldwide standardization. National bodies that are
members of ISO or IEC participate in the development of International Standards through technical
committees established by the respective organization to deal with particular fields of technical
activity. ISO and IEC technical committees collaborate in fields of mutual interest. Other international
organizations, governmental and non-governmental, in liaison with ISO and IEC, also take part in the
work.
The procedures used to develop this document and those intended for its further maintenance
are described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria
needed for the different types of document should be noted. This document was drafted in
accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives or
www.iec.ch/members_experts/refdocs).
Attention is drawn to the possibility that some of the elements of this document may be the subject
of patent rights. ISO and IEC shall not be held responsible for identifying any or all such patent
rights. Details of any patent rights identified during the development of the document will be in the
Introduction and/or on the ISO list of patent declarations received (see www.iso.org/patents) or the IEC
list of patent declarations received (see https://patents.iec.ch).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to
the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see
www.iso.org/iso/foreword.html. In the IEC, see www.iec.ch/understanding-standards.
This document was prepared by Joint Technical Committee ISO/IEC JTC 1, Information technology,
Subcommittee SC 38, Cloud computing and distributed platforms.
Any feedback or questions on this document should be directed to the user’s national standards
body. A complete listing of these bodies can be found at www.iso.org/members.html and
www.iec.ch/national-committees.
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© ISO/IEC 2022 – All rights reserved

Introduction
This document provides an overview of the audit of cloud services. ISO/IEC 22123-1 defines the term
cloud auditor while ISO/IEC 17789 describes the cloud computing roles and sub-roles and activities
related to the audit of cloud services. ISO/IEC TR 23187 which describes the interactions between cloud
service partners (CSNs), cloud service customers (CSCs), and cloud service providers (CSPs) provides
some perspectives on the role and responsibilities of a cloud auditor. This is covered in part in Clause 5
as shown in Figure 1.
Figure 1 — Structure of the document
The structure of the document is as follows:
Clause 5 includes an overview of cloud computing and its major roles. This clause also covers the role of
cloud auditor, its responsibilities, and its relationship with other major cloud computing roles.
Clause 6 provides an overview of cloud service audit including an explanation of the relationship
between audit, assessment, compliance, evaluation, assurance and conformity assessment.
Clause 7 builds on the foundation information in Clause 5 to discuss audit specifications and the
challenges associated with a cloud audit.
Clause 8 covers approaches to conducting cloud audit.
Annex A provides information on International Standards relating to audit and frameworks for audit
schemes, certification and authorization.
Annex B is a compilation of available frameworks and standards which can be used for audit schemes,
for certification and for authorization.
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TECHNICAL REPORT ISO/IEC TR 3445:2022(E)
Information technology — Cloud computing — Audit of
cloud services
1 Scope
This document surveys aspects of the audit of cloud services including:
1) role and responsibilities of parties conducting audit and description of the interactions between
the CSC, CSP, and CSN;
2) approaches for conducting audits of cloud services to facilitate confidence in delivering and using
cloud services;
3) examples of available frameworks and standards which can be used for audit schemes, for
certification, and for authorization.
This document builds upon the cloud auditor role as defined in ISO/IEC 17789 and ISO/IEC 22123.
This document is applicable to all types and sizes of organizations that need to plan and conduct
internal or external audits, and that use, provide and support cloud services.
This document is not intended to describe certification or to identify controls that are published
elsewhere.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO/IEC 22123-1:2021, Information technology — Cloud computing — Part 1: Vocabulary
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO/IEC 22123-1 and the following
apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1 Terms related to the use of audit and assessment
3.1.1
assurance
activity resulting in a statement giving confidence that a product, process or service fulfils specified
requirement
[SOURCE: ISO/IEC Guide 2, 15.1]
© ISO/IEC 2022 – All rights reserved

3.1.2
attestation
issue of a statement, based on a decision, that the fulfilment of specified requirements has been
demonstrated
Note 1 to entry: The resulting statement, referred to in the source document as a “statement of conformity”, is
intended to convey the assurance (3.1.1) that the specified requirements have been fulfilled. Such an assurance
(3.1.1) does not, of itself, provide contractual or other legal guarantees.
Note 2 to entry: First-party attestation and third party attestation are distinguished by the terms declaration,
certification (3.1.4) and accreditation, but there is no corresponding term applicable to second party attestation.
[SOURCE: ISO/IEC 17000:2020, 7.3]
3.1.3
authorization
privileges that give access to designated activities
[SOURCE: ISO 11442:2006, 3.5]
3.1.4
certification
third party attestation (3.1.2) related to an object of conformity assessment (3.1.6), with the exception of
accreditation
[SOURCE: ISO/IEC 17000:2020, 7.6]
3.1.5
certification audit
audit (3.2.2) carried out by an auditing organization independent of the client and the parties that rely
on certification (3.1.4), for the purpose of certifying the client’s management system
Note 1 to entry: In the definitions which follow, the term “audit” has been used for simplicity to refer to third
party certification audit.
Note 2 to entry: Certification audits include initial, surveillance, re-certification audits, and can also include
special audits.
Note 3 to entry: Certification audits are typically conducted by audit teams of those bodies providing certification
(3.1.4) of conformity to the requirements of management system standards.
Note 4 to entry: A joint audit (3.2.11) is when two or more auditing organizations cooperate to audit a single
client.
Note 5 to entry: A combined audit (3.2.9) is when a client is being audited against the requirements of two or more
management systems standards together.
Note 6 to entry: An integrated audit is when a client has integrated the application of requirements of two or
more management systems standards into a single management system and is being audited against more than
one standard.
[SOURCE: ISO/IEC 17021-1:2015, 3.4]
3.1.6
conformity assessment
demonstration that specified requirements are fulfilled
Note 1 to entry: The process (3.1.8) of conformity assessment as described in the functional approach in Annex A
can have a negative outcome, i.e. demonstrating that the specified requirements are not fulfilled.
Note 2 to entry: Conformity assessment includes activities defined elsewhere in the source document, such as
but not limited to testing, inspection, validation, verification, certification (3.1.4), and accreditation.
© ISO/IEC 2022 – All rights reserved

Note 3 to entry: Conformity assessment is explained in Annex A as a series of functions. Activities contributing to
any of these functions can be described as conformity assessment activities.
Note 4 to entry: The source document does not include a definition of “conformity”. “Conformity” does not feature
in the definition of “conformity assessment”. Nor does the source document address the concept of compliance.
[SOURCE: ISO/IEC 17000:2020, 4.1]
3.1.7
compliance
compliant
meeting or exceeding all applicable requirements of a standard or other published set of requirements
[SOURCE: ISO/TR 19591:2018, 3.60]
3.1.8
process
set of interrelated or interacting activities that use inputs to deliver an intended result
[SOURCE: ISO 19011, 3.24]
3.2 Terms related to cloud service audit
3.2.1
assessment
process of collecting and analyzing outcomes to determine course of actions
3.2.2
audit
systematic, independent and documented process (3.1.8) for obtaining objective evidence (3.2.12) and
evaluating it objectively to determine the extent to which the audit criteria are fulfilled
Note 1 to entry: Internal audits (3.2.10), sometimes called first-party audits, are conducted by, or on behalf of, the
organization itself.
Note 2 to entry: External audits include those generally called second and third party audits. Second party audits
are conducted by parties having an interest in the organization, such as customers, or by other individuals on
their behalf. third party audits are conducted by independent auditing organizations, such as those providing
certification (3.1.4)/registration of conformity or governmental agencies.
[SOURCE: ISO 19011:2018, 3.1]
3.2.3
cloud service audit
audit (3.2.2) of the provision and use of one or more cloud services
Note 1 to entry: An audit of a cloud service can include cloud characteristics, cloud deployment, cross cutting
aspects and related management and security functions.
3.2.4
audit client
organization or person requesting an audit (3.2.2)
Note 1 to entry: In the case of internal audit (3.2.10), the audit client can also be the auditee (3.2.7) or the
individual(s) managing the audit programme. Requests for external audit can come from sources such as
regulators, contracting parties or potential or existing clients.
[SOURCE: ISO 19011:2018, 3.12]
© ISO/IEC 2022 – All rights reserved

3.2.5
audit programme
arrangements for a set of one or more audits (3.2.2) planned for a specific time frame and directed
towards a specific purpose
[SOURCE: ISO 19011:2018, 3.4]
3.2.6
audit scope
extent and boundaries of an audit (3.2.2)
Note 1 to entry: the audit scope generally includes a description of the physical and virtual-locations, functions,
organizational units, activities, and processes, as well as the time period covered.
Note 2 to entry: A virtual location is where an organization performs work or provides a service using an on-line
environment allowing individuals irrespective of physical locations to execute processes.
[SOURCE: ISO 19011:2018, 3.5]
3.2.7
auditee
organization as a whole or parts thereof being audited
[SOURCE: ISO 19011:2018, 3.13]
3.2.8
auditor
person who conducts an audit (3.2.2)
[SOURCE: ISO 9000:2015, 3.13.15]
3.2.9
combined audit
audit (3.2.1) carried out together at a single auditee (3.2.7) on two or more management systems
Note 1 to entry: When two or more discipline-specific management systems are integrated into a single
management system this is known as an integrated management system.
[SOURCE: ISO 9000:2015, 3.13.2, modified]
3.2.10
internal audit
audit (3.2.2) conducted by, or on behalf of, an organization itself for management review and other
internal purposes, and which can form the basis for an organization’s self-declaration of conformity
Note 1 to entry: In many cases, particularly in smaller organizations, independence can be demonstrated by the
freedom from responsibility for the activity being audited.
[SOURCE: ISO 22300:2021, 3.1.134]
3.2.11
joint audit
audit (3.2.2) carried out at a single auditee (3.2.7) by two or more auditing organizations
[SOURCE: ISO 9000:2015, 3.13.3]
3.2.12
objective evidence
data supporting the existence or verity of something
Note 1 to entry: objective evidence can be obtained through observation, measurement, test or by other means.
© ISO/IEC 2022 – All rights reserved

Note 2 to entry: objective evidence for the purpose of the audit (3.2.2) generally consists of records, statements
of fact, or other information which are relevant to the audit criteria and verifiable.
[SOURCE: ISO 9000:2015, 3.8.3]
3.2.13
party
natural person or legal person, whether or not incorporated, or a group of either
[SOURCE: ISO/IEC 22123-1:2021, 3.4.1]
4 Abbreviated terms
BCR binding corporate rules
Cloud SLA cloud service level agreement
CSA cloud service agreement
CSC cloud service customer
CSN cloud service partner
CSP cloud service provider
CSU cloud service user
FISMA The Federal Information Security Modernization Act of 2014 (FISMA 2014) (US)
GDPR General Data Protection Regulation (EU GDPR)
HSPD-12 Homeland Security Presidential Directive 12 (US)
ISMS information security management system
IT information technology
LGPD Brazil’s Lei Geral de Proteção de Dados
PCIDSS Payment Card Industry Data Security Standard
PIA Privacy impact assessment
PIMS Privacy information management system
SDOC Suppliers Declaration of Conformity
SLO cloud service level objective
SQO cloud service qualitative objective
5 Overview of cloud computing and the activities of a cloud auditor
5.1 Overview of cloud computing
5.1.1 General
Cloud computing, as defined in ISO/IEC 22123-1:2021, 3.2.1, is a paradigm for enabling network access
to a scalable and elastic pool of shareable physical or virtual resources with self-service provisioning
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and administration on-demand. The cloud computing paradigm is comprised of cloud computing roles
and activities, cloud capabilities types and cloud service categories, cloud deployment models, key
characteristics and cross cutting aspects as shown in Figure 2.
Figure 2 — Overview of cloud computing
5.1.2 Cloud computing roles, sub-roles and activities
In the context of cloud computing and of particular importance to this document is the clarification of
the different roles and their activities. ISO/IEC 22123-1 identifies the major roles of cloud computing
and ISO/IEC 17789 expands on the roles to include sub-roles activities, and their relationship to the
functional components and functional layers of cloud computing.
The major cloud computing roles are:
— Cloud service customer (CSC) is a party which is in a business relationship for the purpose of using
cloud services.
— Cloud service provider (CSP) is a party which makes cloud services available.
— Cloud service partner (CSN) is a party which is engaged in support of, or auxiliary to, activities of
either the CSP or the CSC, or both.
In performing the role, the party (3.2.13) can take on more than one sub-set of the cloud computing
activities of a given role. ISO/IEC TR 23187: provides an overview of and guidance on interactions
© ISO/IEC 2022 – All rights reserved

between cloud service partners (CSNs), specifically cloud service brokers, cloud service developers and
cloud auditors, with CSPs and CSCs.
ISO/IEC 22123-1 and ISO/IEC 17789 do not claim to describe all possible CSN sub-roles. These standards
have identified three initial sub-roles of the CSN: the cloud service broker, the cloud service developer,
and the cloud auditor. A CSN supports the CSC or CSP or both in delivering or using the cloud services.
In the use of cloud computing and in carrying out the activities of each role, an audit client can be a CSC,
CSP or CSN. Through the delivery and use of cloud services, interaction and related activities initiated
by one party can influence responsive activities from another party or parties.
5.2 Overview of the activities of a cloud auditor
5.2.1 Cloud auditor
Auditors of cloud services and more generally of management systems are required to conduct
independent assessments of the CSC’s system specific controls for its cloud services. These potentially
address stored data, applications, operations, performance, privacy and security of the cloud
implementation. Security measures that the CSP implements and operates are also included.
The cloud auditor is further responsible for assessing the CSC’s cloud-specific controls. The audit
specification criteria vary and can depend on many factors. The audit specifications (see Clause 7)
can be set in collaboration with the CSP, by the cloud auditor alone, by standards set independently or
possibly as required by law.
Since the cloud auditor’s defined audit responsibilities cover both the use and provision of cloud
services, the auditor can conduct the audit for the CSP, the CSC or both organizations.
The cloud auditor can perform both internal and external audits.
© ISO/IEC 2022 – All rights reserved

Key
CSC responsibilities
CSP responsibilities
Figure 3 — An example of CSP and CSC responsibilities
Shared responsibility as illustrated in Figure 3 means the audit criteria specifications vary depending
on the cloud deployment model and the cloud services being implemented. It is the responsibility of
an auditor to have a comprehensive understanding of these implementation in order to establish clear
boundaries and ownership of the security controls that are to be audited. It is important to note that a
CSC can use a CSP’s third party attestations as evidence that the requirements associated with the CSP
have been satisfied.
5.2.2 Responsibilities of a cloud auditor
A cloud auditor’s primary responsibility is to conduct audit to the agreed specifications, policies and
agreements.
The specifications (see Clause 7) can include standards defined by the CSP, CSC or cloud auditor,
standards defined independently, or standards required by law. Certification provided by CSPs and
third party suppliers can be evaluated and considered in the result of the audit. The CSP sets the policies
for auditing CSP’s infrastructures and services.
© ISO/IEC 2022 – All rights reserved

All agreements are based on the negotiated cloud service agreement (CSA) or cloud service level
agreement (cloud SLA).
In addition, ISO/IEC 17789:2014, A.4 states that the cloud auditor’s activities focus on the following
categories of audits:
— security audit: see 6.3.4.3;
— privacy audit: see 6.3.4.4;
— performance audit: see 6.3.4.5.
Many principles help to make an audit an effective and reliable tool. ISO 19011 discusses principles that
provide critical guidance to auditors or cloud auditors in performing their tasks including integrity,
fair presentation, professional care, confidentiality, independence, evidence-based approach and risk-
based approach. In addition, an understanding of the relationship between transparency, assurance
and accountability is a relevant contributor to audit quality.
In addition, the following practises are helpful to ensure an audit is an effective and reliable tool as well
as maintain compliance with local laws or regulations:
— Audits can be conducted in a risk-based manner, taking into account concerns regarding the
organizational burden for both the outsourcing institution and the cloud service provider, as well
as practical, security, and confidentiality concerns regarding access to certain types of business
premises or data in multi-tenant environments.
— Audits are subject to the principle of proportionality; they are to be applied in a manner that is
appropriate, taking into account, in particular, the institution’s size and internal organization and
the nature, scope and complexity of its activities.
— Auditors have a professional duty to preserve their objectivity and to avoid conflicts of interest.
(Customer audit requirement).
— Auditors are expected to treat all information received as strictly confidential and handle with due
care. (Customer audit requirement).
— Auditors usually are compliant with generally accepted international professional standards for
auditing and with a code of ethics, one such example is the International Professional Practices
Framework (IPPF) issued by the Institute of Internal Auditors of North America (IIA).
5.2.3 Cloud auditor’s cloud computing activities
The cloud auditor can conduct the audit for the CSP, CSC, or both. The cloud audit can include both
internal (see 6.3.2) and external audits (see 6.3.3). ISO 19011:2018, 5.4.1 discusses the role and
responsibilities of the individual(s) managing an audit programme, and ISO 19011:2018, 5.4.2 explains
the competence of the individual(s) managing the audit programme.
ISO 19011:2018, 5.2 lays out objectives for an audit programme and the auditor’s activities can be
aligned with establishing those audit programme objectives. The individual(s) conducting an audit of
cloud services can refer to those guidelines.
The auditors in conducting an internal or external audit of a cloud-based IT system have to exercise
professional judgement to complete the audit in response to the audit request. In completing the audit
for compliance to SOC 2, for example, the auditor in his/her finding can point to pertinent standards
previously not being considered or overlooked by the requester. This calls into the recommendation
that the auditors need to have appropriate continual development activities to maintain the necessary
competency and knowledge in, e.g. information security, data protection and cloud computing system.
© ISO/IEC 2022 – All rights reserved

5.2.4 Relationship of the cloud auditor to CSPs, CSCs, and other CSNs
The cloud auditor interacts with the CSC and CSP in its auxiliary role. In performing its activities, the
cloud auditor inevitably interacts with other CSN sub-roles such as the cloud service developer and
cloud service broker. The relationship is closely dependent on the roles involved in the use and provision
of cloud services as explained in ISO/IEC TR 23187, Clause 6. For example, a party can play more than
one role as a provider of application capabilities type and be using infrastructure capabilities type from
a CSP. A clear delineation of roles, relationship and activities is essential in establishing the audit scope
and objectives. Depending on the objectives of the audit result, the cloud auditor is to work with CSCs,
CSPs or audit clients (organizations requesting audits), and align its audit specifications (see Clause 7)
appropriately to standards and laws (see 7.5).
ISO/IEC TR 23187 presents several illustrative scenarios of a cloud computing environment whereby
cloud auditor identifies the activities performed in relation to the use or provision of the cloud
service as part of planning the audit objectives. ISO/IEC 17789 and ISO/IEC 22123-1 explicitly assign
the responsibility for providing cloud services to the CSP. Cloud services are being offered in many
incongruent forms and sizes. The “provider” of the cloud service can be offering capabilities such
as data storage and computing power or access to an application. The activities of a CSP can include
data handling, processing data, processing for storage directly or through outsourcing services and
managing the cloud service for users or for a CSP. The cloud auditors establish a good understanding of
the context, the delivery of the cloud services, and the roles, responsibilities and relationship among the
roles.
The cloud auditor can work independently or as a member of an auditing team. It is possible for an
organization to assemble an internal assessment and audit. This audit team will be responsible to
the organization’s audit processes, activities, functions or locations and, as appropriate, authority for
decision-making. In this capacity, the individual auditor is most likely responding to and working with
senior management and critical stakeholders within the organization.
6 Overview of the audit of cloud services
6.1 General
A cloud service audit is defined in this document as an audit of the provision and use of cloud services,
and it is described in 8.4.1.2 in ISO/IEC 17789:2014 to assess a system specific controls against a
specified set of audit criteria to ensure that they have been satisfied. A cloud service audit is not
independent from auditing of an organization’s system and it is helpful to consider as integral part of
the entire system.
The adoption of cloud computing requires important changes to many CSC business processes. The
CSPs have varied business specific needs. The selection of cloud deployment models, cloud services,
and CSPs includes certain complexities since the CSCs select solutions to integrate and interoperate
with their infrastructure that are all built and run differently. The concerns as well as benefits of using
cloud services, provisioning capabilities and resources, and responsibilities for CSCs and CSPs covered
in Clauses 6 and 7 are elements to be considered in the design and implementation of an audit. This can
contribute to the strategies and plans for the journey to implement cloud computing.
ISO/IEC 27017 provides guidelines for information security controls applicable to the provision and use
of cloud services. It includes implementation guidance for relevant controls specified in ISO/IEC 27002
and additional controls with implementation guidance that specifically relate to cloud services. The
criteria specifications vary and are dependent on several factors. A CSC or an external third party
auditor contracted by the CSC can conduct an external audit, i.e. a second party audit on a CSP. It is
important to note that a CSC can use a CSP’s third party attestations as evidence that the requirements
associated with the CSP have been satisfied.
© ISO/IEC 2022 – All rights reserved

6.2 Objectives of an audit of cloud service
6.2.1 General
Cloud computing enables network access to physical or virtual resources and transforms traditional
business information technology (IT) services. It offers benefits associated with the key characteristics
(see Figure 2) and the use of cloud services also requires diligence and care in planning and strategies.
The evidence obtained from audits (3.2.2) and cloud service audits (3.2.3) can help to provide clarity
and understanding to the use of cloud services and in planning for their future developments.
A cloud service audit (3.2.3) offers a practical value to the CSCs or audit client, and it is applicable to all
types and sizes of organizations. CSUs are persons who expect to trust that the cloud service products
are deemed secure to use or deploy cloud service; and have confidence that the CSP(s) will have the
appropriate security processes in place to maintain their security posture. In order to build trust, cloud
service audits (3.2.3) have an important purpose of cloud computing.
The CSCs in some circumstances, can seek assurance in determining the adoption of suitable cloud
service strategy to meet their business specific needs (6.2.4 and 7.4) and selecting the best solution with
a CSP or CSPs. There are a few contributors to the challenges: In the cloud computing environment, the
management responsibilities are shared between CSCs and CSPs. It is not a simple task for one party to
monitor and manage one’s environment and it is added complexity in sharing responsibilities without
clear visibility of the other environment. CSCs and CSPs have separate and different configurations,
governance practises and policies for addressing each environment.
An audit or a cloud audit is a good start for assessing the organization’s system compatibility for adoption
of the use of cloud computing. It can provide evaluation and comparison of the service offerings before
acquisition, determination of potential planning for expanding use of cloud services or for preparation
for cyber insurance and auditing the system for continued use of cloud services.
6.2.2 Audit objectives
An audit (3.2.2) focuses on obtaining objective evidence (3.2.12) and evaluating it objectively to
determine the extent to which the audit criteria are fulfilled. The types of audit performed include
security, privacy impact and performance. A cloud service audit (3.2.3) typically includes some of all of
the following as evidence (depending on who the cloud auditor is responsible to not everything in this
typical list will apply):
— fundamentals and impact of cloud computing;
An objective of a cloud audit is to determine the impact of cloud computing on the organization’s
systems and its boundaries. This includes:
— different types of cloud computing architectures and service delivery models;
Cloud architecture bring together the necessary components and capabilities to connected to
allow applications to run on e.g. cloud capabilities types (see Figure 2). As every organization
and every CSP has their own unique environment that result in different types of cloud
computing. architectures and service delivery models are unique in every organization.
Assessment is to navigate challenges (7.14) and security threats to adopting a cloud computing
architecture.
— dif
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