ISO/IEC TR 5895:2022

Cybersecurity — Multi-party coordinated vulnerability disclosure and handling

This document clarifies and increases the application and implementation of ISO/IEC 30111 and ISO/IEC 29147 in multi-party coordinated vulnerability disclosure (MPCVD) settings, including the evolving commonly adopted practices in this area, by articulating: — The MPCVD life cycle and application of coordinated vulnerability disclosure (CVD) stages (preparation, receipt, verification, remediation[1] development, release, post-release) in MPCVD settings. — Stakeholders involved in MPCVD include users, vendors (coordinating, mitigating, and dependent vendors), reporters, and non-vendor coordinators (entities defined in ISO/IEC 29147 and ISO/IEC 30111). — The exchange of information between stakeholders during the vulnerability handling and disclosure process in a MPCVD settings. Clarifying the application of ISO/IEC 30111 and ISO/IEC 29147 in MPCVD settings illustrates the benefits of vulnerability disclosure processes. [1] Remediation is a defined term used in ISO/IEC 30111 and ISO/IEC 29147. This document uses the term "remediation" and verb “remediate” in the context of this definition.

Cybersécurité — Divulgation et traitement de vulnérabilité coordonnée entre plusieurs parties

General Information

• Status: Published
• Publication Date: 16-Jun-2022
• ICS: 35.030 - IT Security
• Technical Committee: ISO/IEC JTC 1/SC 27 - Information security, cybersecurity and privacy protection
• Drafting Committee: ISO/IEC JTC 1/SC 27 - Information security, cybersecurity and privacy protection
• Current Stage: 6060 - International Standard published
• Start Date: 17-Jun-2022
• Completion Date: 17-Jun-2022

Standards Content (Sample)

TECHNICAL ISO/IEC TR
REPORT 5895
First edition
2022-06
Cybersecurity — Multi-party
coordinated vulnerability disclosure
and handling
Cybersécurité — Divulgation et traitement de vulnérabilité
coordonnée entre plusieurs parties
Reference number
© ISO/IEC 2022
© ISO/IEC 2022
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
ISO copyright office
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Published in Switzerland
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© ISO/IEC 2022 – All rights reserved

Contents Page
Foreword .v
Introduction . vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Concepts . 1
4.1 General . 1
4.2 Relationship with other International Standards . 3
4.2.1 I SO/IEC 29147 - Vulnerability disclosure . 3
4.2.2 I SO/IEC 30111 - Vulnerability handling processes . 3
4.2.3 Risk reduction effectiveness . 4
5 MPCVD scenarios . 5
5.1 General . 5
5.2 MPCVD led by the vendor-coordinator (the owner of the technology developed) –
the “mitigating vendor” . 5
5.3 MPCVD process in non-owner cases . 5
6 MPCVD stakeholders .5
6.1 General . 5
6.2 Vendor . 5
6.2.1 Mitigating vendor . 5
6.2.2 Dependent vendor . 6
6.2.3 Mitigating vendor and coordination . 6
6.3 Non-vendor coordinator . . 6
6.4 Reporters . 6
6.5 Users . 6
6.6 Product security incident response team (PSIRT) function . 6
7 MPCVD life cycle . 6
7.1 General . 6
7.2 Policy development . 7
7.2.1 Preparation . 7
7.2.2 Policy . 7
7.3 Strategy development . 7
7.3.1 Information sharing strategy . 7
7.3.2 Disclosure strategy . 7
7.4 Know your customers . 8
7.5 Encrypted communication methods and conference calls . 8
7.6 Processes and controls . 8
8 MPCVD life cycle for each product .8
8.1 Product and user mapping . 8
8.2 Component analysis . 8
8.3 User analysis . 9
9 MPCVD life cycle for each vulnerability . 9
9.1 Receipt. 9
9.2 V erification . . 9
9.3 Remediation development . 10
9.4 Release . 10
9.5 Post-release . 10
9.6 Embargo period . 10
10 Information exchange .11
11 Disclosure .12
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© ISO/IEC 2022 – All rights reserved

12 Use case for hardware and further considerations .12
Bibliography .14
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© ISO/IEC 2022 – All rights reserved

Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
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 ISO documents 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
orwww.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 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 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 27, Information security, cybersecurity and privacy protection.
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
Remediation of vulnerabilities in modern technology systems can vary and depend on the nature of the
vulnerable component. Certain vulnerability handling efforts can require multiple ecosystem players
taking action at multiple and interdependent layers within a given information and communication
technology (ICT) system. Mitigation can necessitate the engagement of the broad ecosystem of
stakeholders to develop, test and deploy mitigations in a manner geared to incentivize adoption by end
users.
For example, a vulnerability in a widely used software library (protocol) can entail action by different
ecosystem players as part of the remediation effort. As another example, a remediation development
and testing for a vulnerability in a hardware component can depend on an operating system running
on the hardware, and require different actions from different operating system providers. Due to
these considerations, multiple vendors need to participate in remediation efforts involving certain
vulnerabilities.
Yet vulnerability disclosure and handling processes as described in ISO/IEC 29147 and
ISO/IEC 30111 primarily focus on processes involving one reporter and one vendor. Further discussion
and considerations are necessary to explain how ISO/IEC 29147 and ISO/IEC 30111 practices apply in
the context of multi-party coordinated vulnerability handling and disclosure (MPCVD).
ISO/IEC 29147 and ISO/IEC 30111:2019, Clause 8 briefly and generally address the complex
situation of MPCVD, where a broader collaboration within the ecosystem is needed to identify and
validate vulnerabilities, develop and test mitigations and finally make them available for end users.
ISO/IEC 30111 refers to these situations as “cases where vendors can share vulnerability information in
order to resolve the issue that involves components from multiple vendors” and provide five examples
of such situations or reasons:
a) A vulnerability which was reported that affects a specific piece of software, but is caused by an
issue in an underlying operating system or hardware.
b) Vulnerabilities in various product implementations of a flawed standard functional specification or
in published algorithms.
c) Vulnerabilities that are naturally induced by so far widely accepted development methodology.
d) Vulnerabilities in commonly used libraries.
e) Vulnerabilities in software components that lack a current maintainer.
The MPCVD effort for a vulnerability in a technology owned and manufactured by the vendor leading
the process – the coordinating vendor, or mitigating vendor manages and leads the coordination effort.
The mitigating vendor (example a) above) can entail different processes from one in which a broader
collaboration is needed and there is no one distinct vendor of the technology (e.g. protocol-level
vulnerabilities) (examples b) to e) above). These examples include both vendor-coordinated MPCVD
and non-owner MPCVD. Recognizing MPCVD can raise unique considerations for vulnerability handling
given the technical and coordination complexities. Several documents have been published to share
norms and best practices in this evolving area. These best practices continue to be developed, iterated
and improved as new challenges arise. This document builds upon these sources and refers to them.
The audience for this document includes, among others, the participants of the MPCVD process such
as vendors (defined in ISO/IEC 29147:2018, 3.4), maintainers, producers, developers, manufacturers,
1)
suppliers , installers, or providers of a product or service, coordinators (including public coordinators),
reporters (e.g. security researchers), and users of information technology products and services.
1) By way of example, when the open source maintainer is leading the coordination effort in the non-owner
MPCVD case or as “dependent vendor”, a “vendor” can also include open-source software maintainers who develop
and distribute code.
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© ISO/IEC 2022 – All rights reserved

TECHNICAL REPORT ISO/IEC TR 5895:2022(E)
Cybersecurity — Multi-party coordinated vulnerability
disclosure and handling
1 Scope
This document clarifies and increases the application and implementation of ISO/IEC 30111 and
ISO/IEC 29147 in multi-party coordinated vulnerability disclosure (MPCVD) settings, including the
evolving commonly adopted practices in this area, by articulating:
— The MPCVD life cycle and application of coordinated vulnerability disclosure (CVD) stages
2)
(preparation, receipt, verification, remediation development, release, post-release) in MPCVD
settings.
— Stakeholders involved in MPCVD include users, vendors (coordinating, mitigating, and dependent
vendors), reporters, and non-vendor coordinators (entities defined in ISO/IEC 29147 and
ISO/IEC 30111).
— The exchange of information between stakeholders during the vulnerability handling and disclosure
process in a MPCVD settings.
Clarifying the application of ISO/IEC 30111 and ISO/IEC 29147 in MPCVD settings illustrates the
benefits of vulnerability disclosure processes.
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 29147:2018, Information technology — Security techniques — Vulnerability disclosure
ISO/IEC 30111:2019, Information technology — Security techniques — Vulnerability handling processes
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO/IEC 30111 and ISO/IEC 29147
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/
4 Concepts
4.1 General
MPCVD processes are generally based on two concepts: (1) when security vulnerabilities arise, vendors
work quickly, collaboratively and effectively to mitigate the vulnerabilities, and (2) all involved parties
(which includes the various entities working on the mitigations and the reporters who discovered
2) Remediation is a defined term used in ISO/IEC 30111 and ISO/IEC 29147. This document uses the term
"remediation" and verb “remediate” in the context of this definition.
© ISO/IEC 2022 – All rights reserved

or reported the vulnerabilities, if applicable) simultaneously take steps to decrease the risk that
information about the vulnerabilities becomes publicly available before mitigations are available, in
order to protect end users.
The implication for MPCVD is that processes can take a longer period than in other environments (such
as traditional CVD processes involving one entity in the handling processes) to fully develop, validate
and deploy mitigations while information concerning the vulnerability is simultaneously kept in
confidence (often termed, “embargo”) to protect end users from potential exploitation. The embargo
period is during the vulnerability handling process but prior to public disclosure, during which
information concerning the vulnerability is kept in confidence and only shared with entities necessary
for the remediation development process. Similar to other CVD processes, MPCVD processes rely on
the notion that information concerning the vulnerability is generally publicly disclosed only after
mitigations are available to end users.
The MPCVD effort for a vulnerability in a technology owned and manufactured by the vendor leading
the process can entail different processes from one in which a broader collaboration is needed and
there is no one distinct vendor of the technology (e.g. protocol-level vulnerabilities).
MPCVD processes, generally include a higher level of complexity and involvement by a wide range of
stakeholders in the various stages of CVD, as shown in Figure 1. For example, generally the MPCVD
process cases where there is a security vulnerability affecting hardware often need broader
collaboration within the ecosystem. Mitigation of vulnerabilities in hardware can require acting at
multiple and interdependent layers within a given computing system. This, in turn, can necessitate the
engagement of a larger number of third-party participants to develop, test and deploy mitigations in
a manner most likely to incentivize adoption by end users. Mitigation of a hardware vulnerability can
require updates to processor microcode and/or firmware, as well as interdependent updates to the
operating system software or other system software. These updates are then delivered to end-users
through multiple channels, including operating system (OS) and virtualization vendors, cloud service
providers (CSP) or original equipment system manufacturers (OEM). Hardware manufacturers often
do not have a means to unilaterally deliver mitigations without the direct participation of such entities
in the global supply chain.
Figure 1 — Example of vendor-coordinator led MPCVD process — coordinated vulnerability
[1]
disclosure in hardware systems
© ISO/IEC 2022 – All rights reserved

4.2 Relationship with other International Standards
4.2.1 ISO/IEC 29147 - Vulnerability disclosure
ISO/IEC 29147 is used in conjunction with this document. The relationship between the two documents
is shown in Figure 2.
ISO/IEC 29147 provides guidelines for vendors on how to process and remediate potential vulnerabilities
reported by internal or external individuals or organizations. While this document deals with the
interface between multiple vendors, layers of customers, cross manufacturer collaborative mitigation
strategies and multiple reporters, ISO/IEC 29147 provides guidelines for vendors to include in their
normal business processes when receiving reports about potential vulnerabilities from external
individuals or organizations and when distributing vulnerability remediation information to affected
users. This document clarifies the application of these disclosure-related processes in MPCVD settings.
4.2.2 ISO/IEC 30111 - Vulnerability handling processes
ISO/IEC 30111 is used in conjunction with this document. The relationship between the two documents
is shown in Figure 2.
ISO/IEC 30111 gives guidelines on how to investigate, process and resolve potential vulnerability
reports. While this document deals with the interface between multiple vendors, layers of customers,
cross manufacturer collaborative mitigation strategies and multiple reporters, ISO/IEC 30111 deals
with internal vendor processes including the triage, investigation and remediation of vulnerabilities,
whether the source of the report is external to the vendor or from within the vendor’s own security,
development or testing teams. This document clarifies the application of these handling-related
processes in MPCVD settings.
© ISO/IEC 2022 – All rights reserved

Figure 2 — The relationship between ISO/IEC 29147 and ISO/IEC 30111 with respect to MPCVD
4.2.3 Risk reduction effectiveness
Similar to the concept of the impact of successful exploitation referred to in ISO/IEC 30111, risk
reduction effectiveness is an element that can be considered in the context of MPCVD. The risk
reduction effectiveness measures the effectiveness of public disclosure and associated mitigation
and/or remediation against the total cost to society if the vulnerability is exploited. Risk reduction
effectiveness is a function that is affected by a variety of uncertainties, such as:
— Malicious attackers gaining knowledge about vulnerabilities from disclosed vulnerability and
mitigation information, increasing exploitation risk.
— Delayed delivery and/or publication of mitigations and vulnerabilities because there are multiple
contributors (e.g. vendors and open source maintainers) that need to be engaged or added to the
engagement.
— The need for collaboration between vendors across the supply chain, either vertically (vendors
participating and supplying various components to the final product) or horizontally (vulnerability-
affected vendors scattered in a supply chain) can increase the coordination period and introduce
unpredictable variables along the process that can impact expectations around timeline/embargo
periods.
© ISO/IEC 2022 – All rights reserved

MPCVD increases the summation of the risk reduction effectiveness. In other words, a primary
purpose of MPCVD is to reduce the potential harm to users and the public by increasing the effective
collaborations in the relevant CVD stages prior the public release, which includes increasing the
completeness and effectiveness of the proposed remediation while incentivizing its adoption by end
users at disclosure.
5 MPCVD scenarios
5.1 General
Clause 5 provides common scenarios of MPCVD in the scope of this document.
5.2 MPCVD led by the vendor-coordinator (the owner of the technology developed) –
the “mitigating vendor”
In the MPCVD case of the vendor-coordinator (e.g. hardware), there is generally a clear owner/developer
of the underlying vulnerable technology who is typically best-situated to lead the coordination effort
as the most technically knowledgeable of the product and component supply chain. For example,
software companies, including operating systems and firmware vendors, and virtualization vendors
can be integral to the process of developing and testing a mitigation for a hardware-based vulnerability
(taking part in the handling processes), which are coordinated and led by the hardware
...