What is a refresh token?¶
A refresh token is a credential used to obtain new access tokens without requiring the user to authenticate again.
It supports long-running access by applications, browsers and devices.
What this means in practice¶
An access token may last only minutes or hours. A refresh token can allow the application to request a replacement and continue operating for much longer.
This means a cloud account may still be accessed after the original login, after the device changes network, or even after the password changes, depending on the provider’s security controls.
Refresh tokens can therefore matter in account-compromise investigations. If one is stolen, an attacker may repeatedly obtain new access tokens without knowing the password.
A refresh token normally carries no direct proof of the person using it. It represents continuing authority granted to an application or session.
Investigators should not attempt to use a recovered token to access a live account without lawful authority, preservation planning and specialist support. Using it may alter records, trigger alerts or affect the evidential environment.
When reviewing the evidence, distinguish the original authentication from later token refresh events. A later cloud action may have occurred without any new user interaction.
What this may show¶
Provider records may show token issue, refresh activity, application identifiers, device information, IP addresses, revocation and security alerts. The level of detail varies between services.
What this does not show on its own¶
The dangerous assumption is that an expired access token ends the account access.
Where access must be secured, changing the password may not be enough. Refresh tokens, active sessions, trusted devices and delegated applications may need to be revoked.
Key takeaway
A refresh token can preserve cloud access long after the original login, so identify when it was issued, how it was used and whether it remained valid after security changes.