The school principal says the system is better than swipe cards because it stops truant kids getting their mates to sign-in for them. But using the Gummi Bear attack, students can make replicas of their own fingerprints from gelatine, the ingredient in Gummi Bears, to forge a replica finger. The attack worked against a bunch of scanners that detect electrical charges within the human body, since gelatine has virtually the same capacitance as a finger's skin.
A litany of fingerprint scanners have fallen victim to bypass methods, many of which are explained publicly in detail on the internet."
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