The method the FBI used to unlock a terrorist's iPhone 5C apparently won't work on any of Apple's newer iPhones.
In a speech Wednesday at Kenyon College in Ohio, FBI director James Comey acknowledged that the agency bought an unspecified "tool" from an outside private party after Apple refused to create new software to allow access to Syed Farook's iPhone 5C, CNN Money reported Thursday.
Apple had argued that a special-purpose version of iOS would not only offer access to the one device but could threaten the security of millions of iPhones.
That doesn't seem to be the case with the encryption-buster the FBI ended up with. That tool supports only a "narrow slice" of iPhones, Comey said, according to InfoWorld.
In other words, it won't work on the iPhone 5S and the entire iPhone 6 series.
The effort to crack the security of the iPhone 5C tied to Farook, one of the shooters in the San Bernardino, California, terrorist attack in December, led to a dramatic clash between the FBI and Apple. That legal battle ended when the agency turned to a third party to crack the phone. Comey didn't name the third party, but some believe it was an Israeli company called Cellebrite, which specializes in extracting data from phones.
Still unresolved are the broader issues: the line between personal privacy and national security, and the merits of encryption, which scrambles data so it can be read only by people with the right access.
Could the unlock method used by the third-party company get released into the wild? Comey said he doesn't believe that would happen, stating that he has a "high degree of confidence that they are very good at protecting it."
The government has not disclosed the method to Apple. It's worried that spilling the beans to the iPhone maker would come back to bite it.
"We tell Apple, then they're going to fix it, then we're back where we started from," Comey said, according to CNN Money. "We may end up there, we just haven't decided yet."
Apple did not immediately respond to CNET's request for comment.