User verification is a local approval step that proves a real person is present before an authenticator releases a credential. Common methods include a PIN, fingerprint, or face check. In passkey systems, user verification helps ensure that possession of a device is not enough by itself; the user must also unlock the private key with a local gesture or secret.
This matters because cyber attackers often try to bypass the last mile of authentication. If malware compromises a Windows endpoint, it may abuse the local trust chain, capture an already-unlocked session, or trigger verification flows on the victim’s machine. Defenders treat user verification as one layer, not a complete control: strong device security, hardware-backed authenticators, least privilege, and prompt malware cleanup are needed to keep the verification step meaningful.