ISO 27001:2022 Annex A 5.17 Authentication information

In this guide, I will show you exactly how to implement ISO 27001 Annex A 5.17 and ensure you pass your audit. You will get a complete walkthrough of the control, practical implementation examples, and access to the ISO 27001 templates and toolkit that make compliance easy.

I am Stuart Barker, an ISO 27001 Lead Auditor with over 30 years of experience conducting hundreds of audits. I will cut through the jargon to show you exactly what changed in the 2022 update and provide you with plain-English advice to get you certified.

Key Takeaways: ISO 27001 Annex A 5.17 Authentication Information

ISO 27001 Annex A 5.17 requires organizations to control the allocation and management of authentication information (passwords, PINs, biometrics, or tokens) through a formal management process. This control ensures that the “secrets” used to prove an identity remain confidential and are handled securely throughout their entire lifecycle. The goal is to prevent unauthorized access by ensuring that authentication data is never shared, easily guessed, or left in clear text.

Core requirements for compliance include:

• Secure Allocation: You must have a process for creating and distributing initial credentials. Temporary passwords should be unique, complex, and forced to change upon first login.
• Identity Verification: Before issuing new or replacement credentials (e.g., a password reset), you must verify the identity of the requester to prevent social engineering attacks.
• Password Management Systems: Organizations should use systems that enforce strong password criteria (length and complexity) and protect stored credentials using industry-standard encryption.
• User Awareness: Personnel must be briefed on their responsibilities, such as not sharing passwords, avoiding reuse across different sites, and using a vetted Password Manager.
• MFA Implementation: While not explicitly mandated by the text of A.5.17, the 2022 standard strongly implies the use of Multi-Factor Authentication (MFA) for sensitive or remote access as a best-practice management process.
• Change Mandatory Defaults: Any default manufacturer passwords or PINs must be changed immediately upon system installation.

Audit Focus: Auditors will look for “The Credential Gap”:

1. Reset Procedures: “If I call your IT helpdesk and say I’ve forgotten my password, how do they verify it’s really me before resetting it?”
2. MFA Everywhere: “Show me your login screen for your email and VPN. Do they require MFA? If not, how do you justify the risk of using only single-factor authentication?”
3. Password Hygiene: They may perform “desk checks” to look for written passwords (post-it notes) or ask employees how they generate and store their secrets.

User Responsibility Checklist (Audit Prep):

Rule Category	Recommended Action (Do)	Prohibited Action (Don’t)
Storage	Use a vetted Password Manager.	Write it on a Post-It note or in a file.
Sharing	Delegate access via separate IDs.	Text or email your password to a colleague.
Complexity	Use long Passphrases.	Use simple words like “Password123.”
Reuse	Unique credentials for every site.	Use the same password for Work and Social.
MFA	Approve only requests you triggered.	Approve random push notifications (fatigue).

What is ISO 27001 Annex A 5.17?

ISO 27001 Annex A 5.17 is about authentication information which is about providing a way for people to prove they are who they say there when accessing systems or information.

ISO 27001 Annex A 5.17 Authentication Information is an ISO 27001 control that requires an organisation to mange the full life cycle of authentication information.

Authentication information is the information that is used to gain access to systems and resources.

ISO 27001 Annex A 5.17 wants this to be managed. Which seems sensible.

ISO 27001 Annex A 5.17 Purpose

The purpose of ISO 27001 Annex A 5.17 is a preventive control that ensures proper entity authentication and prevents failures of authentication processes.

ISO 27001 Annex A 5.17 Definition

The ISO 27001 standard defines ISO 27001 Annex A 5.17 as:

Allocation and management of authentication information should be controlled by a management process, including advising personnel on the appropriate handling of authentication information.

ISO 27001:2022 Annex A 5.17 Authentication Information

Watch the ISO 27001 Annex A 5.17 Tutorial

In the video ISO 27001 Authentication Information Explained – ISO27001:2022 Annex A 5.17 show you how to implement it and how to pass the audit.

ISO 27001 Annex A 5.17 Podcast

In this episode: Lead Auditor Stuart Barker and team do a deep dive into the ISO 27001 Annex A 5.17 Authentication Information. The podcast explores what it is, why it is important and the path to compliance.

How to implement ISO 27001 Annex A 5.17

Allocating the authentication information

When it comes to creating the passwords and pins that will be used you may want to consider generating them automatically. This can make the process more efficient. To consider is

1. Creating temporary authentication information for first time use
2. Making sure the temporary authentication is hard to guess and unique for each person
3. That it must be changed on first use.

We do not want to give access to any old Tom, Dick or Harry so you will have a way to check and verify the identity of any person making the request and any person being given new, updated or replacement credentials. They may, or may not, be the same person.

When we send authentication information to people we are going to do it in a secure way. We are not going to email it or send it in clear text where possible.

The standard wants a step where the user acknowledges that they have received this information.

We keep a record of what we have allocated and what we have managed and we protect that record.

Lastly if a vendor or supplier provides for default passwords, pins and authentication information we change that immediately.

What is the user responsible for?

Users do have some responsibility. They are not to share their passwords or secret authentication information.

If there is a compromise or a leak then the information and credentials are change immediately that you are notified.

Strong passwords, where passwords are used are implemented. This means passwords should not be easy to guess, or be based on something someone could guess or find out. The example is not to use dictionary words or combinations of. This is actually bullshit as the use of dictionary words to make up a phrase would be an ideal password but the standard thinks it knows better.

Passwords have a minimum length according to the standard which is pure genius as any word has a minimum length. It gives no guidance so choose wisely.

Ideally we do not reuse password across different systems.

Contracts of employment include the obligation to follow these rules.

Guidance on a password management system

General guidance on password management systems, which ever you choose, would be

• Users are allowed to select and change their own passwords
• They enforce strong passwords according to best practice
• They force users to change passwords at first use
• They force password changes as required such as after a security incident
• Ideally they prevent re-use of previous passwords
• They prevent the use of common passwords
• Where possible they take account of compromised accounts and passwords and prevent their use
• They do not display passwords on the screen when being entered
• They do not store or send passwords in clear text
• Passwords should be encrypted

Exceptions

There are many ways in which the standard is still old fashioned and a little out of date. You see this come up a lot where it tells you what to do and then says, but in the real world we know you cannot, so do not.

Some exceptions would be that clearly, other ways to authenticate other than passwords are acceptable. Consider tokens, card, biometrics.

Contrary to the standard there is an argument to not frequently change passwords. It does acknowledge this as a scenario which is good. It is about finding the balance for you based on risk and business need and being able to argue that with an auditor.

User Responsibility Checklist

Rule	Do	Don’t
Storage	Use a Password Manager (e.g., 1Password).	Write it on a Post-It note.
Sharing	Delegate access properly (separate accounts).	Text your password to a colleague.
Complexity	Use Passphrases (e.g., “Correct-Horse-Battery”).	Use “Password123”.
Reuse	Unique password for every site.	Use the same password for Work and Facebook.
MFA	Approve only requests you triggered.	Approve random push notifications.

ISO 27001 Access Control Policy Template

The ISO 27001 Access Control Policy template is pre written and ready to go. It is one of the required ISO 27001 policies that sets out the organisations approach to access control.

How to comply

To comply with ISO 27001 Annex A 5.17 you are going to implement the ‘how’ to the ‘what’ the control is expecting. In short measure you are going to

• Implement a process for creating, updating and removing authentication information

How to pass an ISO 27001 Annex A 5.17 audit

To pass an audit of ISO 27001 Annex A 5.17 you are going to make sure that you have followed the steps above in how to comply.

What the auditor will check

The audit is going to check a number of areas. Lets go through the most common

1. That you have not done something stupid

The auditor is going to check the rules, procedures and access control methodology and make sure you followed them. As with everything having documented evidence of anything you can is going to be your friend. So practical things like authentication information registers, encrypted passwords, approval and allocation processes that you can evidence are in operation. Work through recent hires for example and ensure the processes were followed and look for the gotchas. Is there an approval audit trail. When you log into the system that was approved does the users access match what was requested.

2. That you have rules, processes and you have followed them and have trained people

This is obvious but they are going to look that you have documented what you say you do, that you follow it and that you have trained people.

3. Documentation

They are going to look at audit trails and all your documentation and see that is classified and labelled. All the documents that you show them, as a minimum if they are confidential should be labelled as such. Is the document up to date. Has it been reviewed in the last 12 months. Does the version control match. Doing anything else would be a massive own goal.

Top 3 ISO 27001 Annex A 5.17 Mistakes People Make and How to Avoid Them

The top 3 Mistakes People Make For ISO 27001 Annex A 5.17 are

1. Share authentication information

There are circumstances where people know share authentication information and they do not need to. This is usually just lazy admin. The sharing of accounts where it doesn’t and should be needed.

2. Your temporary passwords are always the same

Giving first time passwords and making them unique may be a little tricky so often people rely on one password they always send out. Something like P@assw@rd. Do not do this.

3. Your document and version control is wrong

Keeping your document version control up to date, making sure that version numbers match where used, having a review evidenced in the last 12 months, having documents that have no comments in are all good practices.

Fast Track ISO 27001 Annex A 5.17 Compliance with the ISO 27001 Toolkit

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Own Your ISMS, Don’t Rent It

Do it Yourself ISO 27001 with the Ultimate ISO 27001 Toolkit

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For ISO 27001 Annex A 5.17 (Authentication information), the requirement is to manage the full lifecycle of authentication secrets, such as passwords, pins, tokens, and biometric data. This ensures that only verified entities can prove their identity and gain access to systems, preventing unauthorised entry and credential theft.

While SaaS compliance platforms often try to sell you “automated password rotation” or complex MFA (Multi-Factor Authentication) reporting modules, they cannot actually enforce a physical behaviour, like stopping an employee from writing a password on a Post-it note, nor can they draft the specific legal obligations for your employment contracts. The High Table ISO 27001 Toolkit is the logical choice because it provides the governance framework you need to manage authentication secrets effectively without a recurring subscription fee.

1. Ownership: You Own Your Authentication Standards Forever

SaaS platforms act as a middleman for your compliance evidence. If you define your password complexity rules and store your credential allocation logs inside their proprietary system, you are essentially renting your own organizational security standards.

• The Toolkit Advantage: You receive the Access Control Policy and User Responsibility Checklist in fully editable Word/Excel formats. These files are yours forever. You maintain permanent ownership of your standards (such as your specific passphrase requirements), ensuring you are always ready for an audit without an ongoing “rental” fee.

2. Simplicity: Governance for the Tools You Already Have

Annex A 5.17 is about controlling the allocation and advising personnel on handling secrets. You don’t need a complex new software interface to manage what 1Password, LastPass, or your existing IT service desk process already does perfectly.

• The Toolkit Advantage: Your team already uses password managers and MFA. What they need is the governance layer to prove to an auditor that these tools are formal, risk-based, and that staff are educated on their use. The Toolkit provides pre-written policies and “User Responsibility Checklists” that formalize your existing technical work into an auditor-ready framework, without forcing your team to learn a new software platform just to log a password reset.

3. Cost: A One-Off Fee vs. The “Credential” Tax

Many compliance SaaS platforms charge more based on the number of “users” or “accounts” you monitor. For a control that applies to every single person and service account in your company, these monthly costs can scale aggressively.

• The Toolkit Advantage: You pay a single, one-off fee for the entire toolkit. Whether you manage 5 sets of credentials or 5,000, the cost of your Authentication Documentation remains the same. You save your budget for actual security hardware (like YubiKeys) rather than an expensive compliance dashboard.

4. Freedom: No Vendor Lock-In for Your Security Strategy

SaaS tools often mandate specific technical ways to report on and monitor authentication. If their system doesn’t match your cloud-native setup or your unique biometric requirements, the tool becomes a bottleneck to efficiency.

• The Toolkit Advantage: The High Table Toolkit is 100% technology-agnostic. You can tailor the Authentication Procedures to match exactly how you operate, whether you use high-end biometrics or simple, risk-managed passphrases. You maintain total freedom to evolve your security strategy without being constrained by the technical limitations of a rented SaaS platform.

Summary: For Annex A 5.17, the auditor wants to see a formal management process for authentication secrets and proof that personnel are advised on proper handling. The High Table ISO 27001 Toolkit provides the governance framework to satisfy this requirement immediately. It is the most direct, cost-effective way to achieve compliance using permanent documentation that you own and control.

ISO 27001 Annex A 5.17 FAQ

Related ISO 27001 Controls

ISO 27001 Annex A 8.5 Secure Authentication

ISO 27001 Annex A 8.21 Security of Network Services

Further Reading

ISO 27001 Access Control Policy Beginner’s Guide

ISO 27001 controls and attribute values

Control type	Information security properties	Cybersecurity concepts	Operational capabilities	Security domains
Preventive	Confidentiality	Protect	Identity and access management	#Protection
	Integrity
	Availability