ISO 27002:2022 – Control 5.20 – Addressing Information Security Within Supplier Agreements

Purpose of Control 5.20

Control 5.20 governs how an organisation forms a contractual relationship with a supplier, based on their security requirements and the type of suppliers they deal with.

5.20 is a preventative control that maintains risk by establishing mutually agreeable obligations between organisations and their suppliers that deal with information security.

Whereas Control 5.19 governs with information security throughout the relationship, Control 5.20 is preoccupied with how organisations form binding agreements from the start of a relationship.

Attributes of Control 5.20

Ownership of Control 5.20

Ownership of Control 5.20 should be dependent on whether or not the organisation operates their own legal department, and the underlying nature of any signed agreement.

If the organisation has the legal capacity to draft, amend and store their own contractual agreements without third party involvement, ownership of 5.20 should rest with the person who holds ultimate responsibility for legally binding agreements within the organisation (contracts, memos of understanding, SLAs etc.)

If the organisation outsources such agreements, ownership of Control 5.20 should rest with a member of senior management that oversees an organisation’s commercial operation, and maintains a direct relationship with an organisation’s suppliers, such as a Chief Operating Officer.

General Guidance on Control 5.20

Control 5.20 contains 25 guidance points that ISO state “can be considered” (i.e. not necessarily all of them) in order to fulfil an organisation’s information security requirements.

Regardless of what measures are adopted, Control 5.20 explicitly states that both parties should exit the process with a “clear understanding” of their information security obligations to one another.

1. A clear description should be provided detailing the information that needs to be accessed in any way, and how that information is going to be accessed.
2. The organisation should classify the information to be accessed in accordance with its published classification scheme (see Control 5.10, Control 5.12 and Control 5.13).
3. Adequate consideration should be given to the supplier-side classification scheme, and how that relates to the organisation’s classification of information.
4. Both parties’ rights should be categorised into four main areas – legal, statutory, regulatory and contractual. Within these four areas, various obligations should be clearly outlined, as is standard in commercial agreements, including accessing PII, intellectual property rights and copyright stipulations. The agreement should also cover how each of these key areas will be addressed in turn.
5. Each party should be obligated to enact a series of concurrent controls that monitor, assess and manage information security risk levels (such as access control policies, contractual reviews, systems monitoring, reporting and periodic auditing). In addition, the agreement should clearly outline the need for supplier personnel to adhere to an organisation’s information security standards (see Control 5.20).
6. There should be a clear understanding of what constitutes both acceptable and unacceptable use of information, and physical and virtual assets from either party.
7. Procedures should be put in place that deal with the levels of authorisation required for supplier-side personnel to access or view an organisation’s information (e.g. authorised user lists, supplier-side audits, server access controls).
8. Information security should be considered alongside the supplier’s own ICT infrastructure, and how that relates to the type of information that the organisation has provided access to, the risk criteria and the organisation’s base set of business requirements.
9. Consideration should be given to what courses of action the organisation is able to take in the event of a breach of contract on the part of the supplier, or failure to comply with individual stipulations.
10. The agreement should clearly outline a mutual Incident Management procedure that clearly stipulates what needs to happen when problems arise, particularly concerning how the incident is communicated between both parties.
11. Personnel from both parties should be given adequate awareness training (where standard training is not sufficient) on key areas of the agreement, specifically concerning key risk areas such as Incident Management and the provision of access to information.
12. Adequate attention should be given to the use of subcontractors. If the supplier is permitted to use subcontractors, the organisations should take steps to ensure that any such individuals or companies are aligned with the same set of information security requirements as the supplier.
13. Where it’s legally possible and operationally relevant, organisations should consider how supplier personnel are screened prior to interacting with their information, and how screening is recorded and reported to the organisation, including non-screened personnel and areas for concern.
14. Organisations should stipulate the need for third-party attestations that verify the supplier’s ability to fulfil organisational information security requirements, including independent reports and third-party audits.
15. Organisations should have the contractual right to assess and audit a supplier’s procedures, relating to Control 5.20.
16. Suppliers should have an obligation to deliver reports (at varying intervals) that cover the effectiveness of their own processes and procedures, and how they intend to address any issues raised in such a report.
17. The agreement should take steps to ensure the timely and thorough resolution of any defects or conflicts that take place during the course of the relationship.
18. Where relevant, the supplier should operate with an robust BUDR policy, in line with the organisation’s needs, that covers off three main considerations:

    a) Backup type (full server, file and folder etc, incremental etc.)
    b) Backup frequency (daily, weekly etc.)
    c) Backup location and source media (onsite, offsite)

19. Data resilience should be achieved by operating with a disaster recovery location that is separate from the supplier’s main ICT site, and is not subject to the same level of risk.
20. The supplier should operate with a comprehensive change management policy that gives advance notification to the organisation of any changes that may affect information security, and provide the organisation with the ability to reject such changes.
21. Physical security controls (building access, visitor access, room access, desk security) should be enacted that are relevant to the kind of information they are permitted to access.
22. When the need arises to transfer information between assets, sites, servers or storage locations, the supplier should ensure that data and assets are protected from loss, damage or corruption throughout the process.
23. The agreement should outline a comprehensive list of actions to be taken by either party in the event of termination (see also Control 5.20), including (but not limited to):

    a) Asset disposal and/or relocation
    b) Information deletion
    c) Return of IP
    d) Removal of access rights
    e) Ongoing confidentiality obligations

24. Further to point 23, the supplier should outline precisely how it intends to destroy/permanently delete the organisation’s information the moment it is no longer required (i.e. in the event of a termination).
25. If, at the end of a contract, the need arises to handover support and/or services to another provider not listed on the agreement, steps are taken to ensure that the process results in zero business interruption.

Supporting controls

• 5.10
• 5.12
• 5.13
• 5.20

Supplementary Guidance

To aid organisations in managing supplier relationships, Control 5.20 states that organisations should maintain a register of agreements.

Registers should list all agreements held with other organisations, and categorised by the nature of the relationship, such as contracts, memorandums of understanding and information-sharing agreements.

Changes and Differences from ISO 27002:2013

ISO 27002:2022-5.20 replaces 27002:2013-15.1.2 (Addressing security within supplier agreements).

ISO 27002:2022-5.20 contains numerous additional guidance thats deal with a broad range of technical, legal and compliance-related topics, including:

• Handover procedures
• Information destruction
• Termination clauses
• Physical security controls
• Change management
• Backups and information redundancy

Broadly speaking, ISO 27002:2022-5.20 puts a much greater emphasis on what occurs at the end of a supplier relationship, and allocates far more importance to how a supplier achieves redundancy and data integrity throughout the course of an agreement.

New ISO 27002 Controls

How ISMS.online Helps

ISO 27002 implementation is simpler with our step-by-step checklist that guides you through the whole process, from defining the scope of your ISMS through risk identification and control implementation.

Get in touch today to book a demo.