Home / ISO 27001 Glossary of Terms / Authentication Information

Authentication Information

13/09/2025

Author: Stuart Barker | ISO 27001 Expert and Thought Leader

Authentication information refers to data that verifies a user’s identity. This info proves you are who you say you are. The most common types are things you know, like a password; things you have, like a phone or a key fob; and things you are, like a fingerprint.

Examples

  • Passwords: The secret word or phrase you type to log in.
  • PINs: The short number you use for your debit card or phone.
  • Security Questions: Questions like “What was your first pet’s name?”
  • Biometrics: Using your body, like a fingerprint or a face scan.
  • Tokens: A small device or a code sent to your phone.

Context

Imagine you want to get into your house. Your key is a form of authentication information because it proves you have permission to enter. Similarly, your password is a key for your digital accounts. For extra security, some systems need more than one key, like a password and a code from your phone. This is called multi-factor authentication (MFA).

Relevant ISO 27001 Controls

The following controls from the ISO/IEC 27001:2022 standard are related to authentication information:

About the author

Stuart Barker is an information security practitioner of over 30 years. He holds an MSc in Software and Systems Security and an undergraduate degree in Software Engineering. He is an ISO 27001 expert and thought leader holding both ISO 27001 Lead Implementer and ISO 27001 Lead Auditor qualifications. In 2010 he started his first cyber security consulting business that he sold in 2018. He worked for over a decade for GE, leading a data governance team across Europe and since then has gone on to deliver hundreds of client engagements and audits.

He regularly mentors and trains professionals on information security and runs a successful ISO 27001 YouTube channel where he shows people how they can implement ISO 27001 themselves. He is passionate that knowledge should not be hoarded and brought to market the first of its kind online ISO 27001 store for all the tools and templates people need when they want to do it themselves.

In his personal life he is an active and a hobbyist kickboxer.

His specialisms are ISO 27001 and SOC 2 and his niche is start up and early stage business.