What is MFA?

1 min read Updated 2026-02-05

Multi-Factor Authentication. A security method requiring two or more verification factors (something you know, have, or are) to access an account.

Understanding MFA

MFA significantly reduces the risk of account compromise by requiring multiple forms of verification. Even if an attacker obtains a password, they still need the second factor. TOTP apps, SMS codes, and hardware keys are common second factors, with hardware keys being the most secure.

Examples

  • Password + TOTP code from an authenticator app
  • Password + SMS verification code
  • Password + hardware security key (YubiKey)
  • Password + biometric verification

How to Prevent

  • Implement MFA for all user accounts, especially privileged ones
  • Prefer authenticator apps or hardware keys over SMS
  • Provide backup codes for account recovery
  • Consider risk-based authentication for additional protection
  • Educate users on the importance of MFA

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