kertakäyttökoodi

Kertakäyttökoodi, often translated as one-time code or single-use code, refers to a sequence of characters or numbers that is valid for a single transaction or session. This security measure is widely employed in various digital contexts to enhance authentication and prevent unauthorized access.

The primary purpose of a kertakäyttökoodi is to add an extra layer of security beyond a static password. When a user initiates a sensitive action, such as logging into an account, authorizing a financial transaction, or resetting a password, the system generates a unique code. This code is typically sent to the user via a secure channel, such as an SMS message to their registered phone number or through a dedicated authenticator application.

The user then needs to enter this kertakäyttökoodi within a specified timeframe to complete the action. Once the code is used or its validity period expires, it becomes invalid, rendering it useless for subsequent attempts. This ephemeral nature is crucial to its security effectiveness, as it mitigates risks associated with intercepted or stolen credentials.

Kertakäyttökoodit are a common component of two-factor authentication (2FA) or multi-factor authentication (MFA) systems, significantly strengthening the security posture of online services. Their implementation helps protect against various cyber threats, including phishing attacks and credential stuffing, by ensuring that even if a primary password is compromised, the attacker cannot gain access without the current, time-sensitive code.