Cybersecurity glossary
What is multi-factor authentication?
Also known as: MFA, 2FA, two-factor authentication
Definition
Multi-factor authentication (MFA) requires two or more kinds of proof to sign in, such as a password plus an app prompt, security key or biometric unlock of a passkey.
Why it matters
MFA blocks most attacks based on stolen passwords. Phishing-resistant methods (FIDO2 security keys and passkeys) are strongest; authenticator apps are good; SMS codes are the weakest common option but still better than a password alone.
Common questions about multi-factor authentication
- What should I do if I clicked a phishing link?
- Should I change my passwords regularly?
- What is multi-factor authentication and do I need it?
- What is business email compromise (BEC)?
- Are password managers safe to use?
- Is SMS two-factor authentication safe?
- How do I check if my email or password was in a data breach?
- What should I do if my email account is hacked?
Sources
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