An access trail is the set of logs and other records that show how accounts, devices, and systems were accessed. It can include authentication events, remote-access connections, session activity, and changes to permissions or account settings.
During a suspected cyber incident, defenders use access trails to check whether access was unauthorized, identify affected accounts and systems, and establish a timeline. Unusual logins, unfamiliar locations, or unexpected privilege changes can signal suspicious activity, though each clue needs validation. Preserve relevant logs promptly, since records may be overwritten or altered; treat them as evidence rather than proof on their own.