A biometric liveness check is a safeguard that tries to confirm a real, present human is performing the scan, rather than a replay, photo, mask, video, or other spoofing aid. It is commonly used with face, fingerprint, or voice verification during onboarding, account recovery, and high-risk authentication.
In cyber security, liveness checks help reduce presentation attacks, where an intruder attempts to fool a biometric system with fake evidence. They matter because biometric data alone is not always proof of presence: a clear image or recorded voice can sometimes pass basic matching. Defenders use challenge-response prompts, motion cues, depth sensing, texture analysis, or device-based signals to raise confidence that the subject is live. Attackers adapt by using injected media, deepfakes, or replay tools, so liveness should be combined with document checks, device binding, and workflow controls.