What evidence do auditors commonly ask for on 8.5 Secure authentication?

An authentication standard linking required authentication strength to information classification and system criticality; MFA configuration and coverage reports for critical systems, remote access and privileged access, including conditional or risk-based rules; Log-on configuration showing warning banners, generic error messages, lockout or throttling after failed attempts and masked password entry; Authentication logs recording successful and failed attempts, with alerting on suspected brute force; Session timeout and connection time limit settings for high-risk applications and locations; Evidence that passwords are not transmitted in clear text, for example TLS enforcement on log-on endpoints.

What is the most common gap auditors find on 8.5?

MFA is enabled for some critical systems but legacy protocols allow bypass

ISO/IEC 27002:2022 · Technological controls

`8.5` Secure authentication

Secure authentication technologies and procedures are to be put in place, driven by the information access restrictions and the access control policy. Purpose: authenticate users and other entities securely whenever they are given access to systems, applications and services. Guidance: choose an authentication technique suited to proving the claimed identity of users, software, messages and other entities, with strength matched to the classification of what is being accessed. When identity must be proven strongly, rely on something other than a password, for example certificates, smart cards, hardware tokens or biometric traits. Access to critical systems should use multi-factor authentication combining something known, held and inherent, which can be extended with rule-based step-up when access comes from an unusual location, device or time. Compromised biometric data should be invalidated, and because biometrics can fail in some conditions (moisture, ageing) at least one alternative technique should be available. Log-on should be designed to minimize unauthorized access by: not revealing sensitive system or application details until log-on succeeds; showing a notice that only authorized users may access the system; giving no help during log-on that could aid an intruder, such as saying which part of the input was wrong; validating the log-on only once all input is complete; resisting brute force through CAPTCHA, forced reset after a set number of failures or lockout; logging failed and successful attempts; raising a security event and alerting the user and administrators when a possible attack on log-on controls is seen; showing or sending separately, after success, when the last successful log-on happened and any failed tries since then; hiding passwords as typed, unless this must be relaxed for accessibility or to avoid repeated lockouts; never sending passwords in clear text across networks; ending sessions after a period of inactivity, especially in public or external locations and on endpoints; and limiting connection times for high-risk applications. Other information: ISO/IEC 29115 covers entity authentication assurance.

Source: ISO/IEC 27002:2022, 8.5. The statement above is our statement of the clause, read from the published text and cited so you can check it against the official text, not the instrument verbatim. Open ISO/IEC 27002:2022 in the compliance library.

ISO/IEC 27002 is guidance on the Annex A controls; certification is against ISO/IEC 27001. Use this set when your sheet follows the 27002 numbering.

artefacts

held by a system

at each review

easy

to go live

Identity provider / directory

where the evidence lives

teal = a system already holds it · olive = produced at each review. To go live: easy when half or more of the artefacts are already held by a system, moderate from a quarter to a half, hard below a quarter.

These are the artefacts auditors commonly ask for on this requirement, our guidance rather than text from the standard. Your assessor decides what is sufficient in your context, and asks for samples across the period when a report covers one.

system holds itEvidence a system already holds

MFA configuration and coverage reports for critical systems, remote access and privileged access, including conditional or risk-based rules · Identity provider / directory
Log-on configuration showing warning banners, generic error messages, lockout or throttling after failed attempts and masked password entry · Identity provider / directory
Authentication logs recording successful and failed attempts, with alerting on suspected brute force · Identity provider / directory
Session timeout and connection time limit settings for high-risk applications and locations · Identity provider / directory

periodic reviewEvidence produced at each review

Evidence that passwords are not transmitted in clear text, for example TLS enforcement on log-on endpoints · Endpoint management (MDM / EDR)

governing documentDocuments that govern the control

An authentication standard linking required authentication strength to information classification and system criticality · Policy repository / GRC workspace

First move

Automate the pull from your Identity provider / directory. Scheduled export of users, roles and MFA state from the directory; access-review completion pulled from the IdP, not a spreadsheet.

Common gaps auditors find

MFA is enabled for some critical systems but legacy protocols allow bypass
Error messages reveal whether the username or the password was wrong
No lockout or rate limiting exists on internet-facing log-on pages
Biometric authentication has no fallback method

Do this for your whole sheet

Paste the rows you run your controls from and get this mapping for every control at once, with the periodic-review ones flagged and a first move per row. No account for the first run.

Build my evidence sheet

8.4 Access to source code · 8.6 Capacity management