To demonstrate why using fingerprints to secure passports is a bad idea, the German hacker group Chaos Computer Club has published what it says is the fingerprint of Wolfgang Schauble, Germany's interior minister.

According to CCC, the print of Schauble's index finger was lifted from a water glass that he used during a panel discussion that he participated in last year at a German university. CCC published the print on a piece of plastic inside 4,000 copies of its magazine Die Datenschleuder that readers can use to impersonate the minister to biometric readers.

Several years ago the CCC published a guide to lifting and reproducing fingerprints.

Schauble is a big proponent of the use of fingerprints in passports but is not the CCC's only target. The group has called for help in obtaining the prints of other German officials, including Chancellor Angela Merkel.

The CCC's publication of the fingerprint coincides this week with the presentation of a security researcher who demonstrated a biometric keylogger that can capture digital fingerprints and other digital biometric data as its transmitted from a scanning device to the server where the information is processed. The hacker can then analyze and re-use the data to subvert biometric systems and gain entry to secured buildings.

Matt Lewis, a researcher with British-based Information Risk Management, demonstrated his Biologger tool at the Black Hat security conference in Amsterdam but said the easy part is intercepting the data – the hard part is getting the biologger onto a network.

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