FBI director James Comey did not reveal the exact process that the agency had followed to gain access to the phone which was used by one of two people responsible for the deaths of 14 Americans in December. But he was quoted as saying, "This doesn't work on 6S, doesn't work on a 5S, and so we have a tool that works on a narrow slice of phones."
But in refusing to tell Apple about the flaw that allowed the FBI to gain access to the data, the agency has left all users of that model open to risk of having their data stolen by anyone with access to the same tool that the FBI used.
Comey was noncommittal when asked about it. "We tell Apple, then they're going to fix it, then we're back where we started from," he said. "We may end up there, we just haven't decided yet," he was quoted as saying.
But as Apple is said to have patched the flaw that allowed this method in iOS 8.1.1, and Rizwan's phone was running iOS 9.0, the FBI looks to have used some other tool that exploited some other vulnerability.
Which makes it very scary for those who are still using an iPhone 5C.
The stoush burst into the news when the FBI obtained a court order on February 16, asking Apple to supply a new version of iOS that did not have certain locking functions, so that the agency could attempt to guess the pass code on the iPhone 5C by using a brute force method. When Apple resisted, the FBI came back with an order compelling the company to fall in line.
The phone in question belongs to the San Bernardino department of health; Rizwan was employed by them.
The matter was scheduled for a court hearing on March 22, but on March 21 the FBI requested a continuance until April 5 in order that a method proposed to it by an outside agency for breaking into the phone could be tested. On March 28, US time, the FBI called off the case, saying that this method had worked and it no longer needed Apple's help.