The Web site IsTouchIDHackedYet this week posted a "bounty" worth $16,000 in cash and prizes for finding a vulnerability in the iPhone 5S, the first smart phone to include a security lock that is opens only when the user's fingerprint matches that of the owner.
CNN said Sunday the system is intended to discourage thieves, but Nick DePetrillo and Robert David Graham said on the Web site they wanted to put Apple's claims to a real-world test.
""The whole point of #istouchidhackedyet was to put up or shut up with regards to criticisms of Apple's Touch ID security and implementation," DePetrillo said Saturday on Twitter.
DePetrillo, who has a reputation for finding ways to hack smart phones, said he actually thought Apple had introduced Touch ID "in a reasonably secure way."
The iPhone 5S went on the market only Friday and was apparently still secure Sunday, CNN said.