Apple iPhone 5s Fooled By Fake Finger

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Hackers from the Chaos Computer Club have shown that the fingerprint scanner in Apple's iPhone 5s can be fooled by an artificial fingerprint made using readily available materials.

The group has posted a video on YouTube that demonstrates the effectiveness of their technique.

In a statement on the group's website, CCC spokesman Frank Rieger warns that fingerprint biometric technology is insecure and unwise as a means of authentication. "It is plain stupid to use something that you can't change and that you leave everywhere every day as a security token," he said. "The public should no longer be fooled by the biometrics industry with false security claims. Biometrics is fundamentally a technology designed for oppression and control, not for securing everyday device access."

[ If Tim Cook says it, does that make it true? Read Apple CEO Cook: We Don't Do Junk. ]

Apple did not respond to a request for comment. Last week, in an apparent attempt to address privacy and security concerns, an Apple spokesman told the Wall Street Journal that the Touch ID system does not store fingerprint images.

Fingerprint scanning systems have a long history of vulnerability to hacking. Working with a German TV show in 2007, the CCC demonstrated that fingerprint authentication technology used by a German supermarket could be duped. The group says that what differentiates Apple's technology from other fingerprint scanners is a higher resolution sensor.

Bypassing Touch ID involves photographing a fingerprint at 2400 dpi resolution, cleaning the image up and then laser printing it at 1200 dpi on a transparent sheet using a heavy toner setting. To the resulting relief pattern, either wood glue or pink latex milk is applied, which hardens to form the surface of the fake fingerprint. The hardened substance is then lifted from the transparent sheet, breathed on for moisture and applied to the iPhone Touch ID scanner to unlock the device.

The CCC posted instructions about how to create a fake fingerprint back in 2004. In the past decade, the risks of fingerprint spoofing have been widely covered in academic research. In 2006, researchers from Washington & Jefferson College reported, "biometric fingerprint scanners can easily be spoofed with Play-doh, gummy bears and other household materials." In 2002, Yokohama National University researchers reported, "artificial fingers that are easily made of cheap and readily available gelatin were accepted by extremely high rates by particular fingerprint devices with optical or capacitive sensors."

Evidently, this is still the case with Apple's technology, though the security community has yet to evaluate the hack. Last week, security researchers Robert Graham and Nick DePedrillo established a crowdsourced bounty program, through the website IsTouchIDHackedYet.com, to reward the first person or group to break Apple's Touch ID system. As of Sunday evening, the website indicated that the CCC's hack may qualify for the bounty, the amount of which remains in question due to conditions placed on a pledge of $10,000 committed by venture capitalist Arturas Rosenbacher.

Learn more about smartphone security and related topics by attending the Interop conference track on Mobility in New York from Sept. 30 to Oct. 4.