This Israeli firm might be helping the FBI break into the San Bernardino iPhone without Apple's help

Israel's Cellebrite, a provider of mobile forensic software, is helping the U.S. Federal Bureau of Investigation's attempt to unlock an iPhone used by one of the San Bernardino, California shooters, the Yedioth Ahronoth newspaper reported on Wednesday.

If Cellebrite succeeds, then the FBI will no longer need the help of Apple Inc, the Israeli daily said, citing unnamed industry sources.

Cellebrite officials declined to comment on the matter.

Apple is engaged in a legal battle with the U.S. Justice Department over a judge's order that it write new software to disable passcode protection on the iPhone used by the shooter.

The two sides were set to face off in court on Tuesday - but on Monday a federal judge agreed to the government's request to postpone the hearing after U.S. prosecutors said a "third party" had presented a possible method for opening the encrypted smartphone.

The development could bring an abrupt end to the high-stakes legal showdown which has become a lightning rod for a broader debate on data privacy in the United States.

Cellebrite, a subsidiary of Japan's Sun Corp, has its revenue split between two businesses: a forensics system used by law enforcement, military and intelligence that retrieves data hidden inside mobile devices and technology for mobile retailers.

It's not clear how the unnamed "outside party" assisted the FBI - whoever they are - intends to gain access to the device. Security researcher Jonathan Zdziarski has speculated (as have others) that it may involve copying the contents of the NAND memory, then overwriting it whenever defensive security mechanisms kick in - allowing the FBI to get past a limit on the number of incorrect passcodes that can be entered before the device wipes itself. Here's Zdziarski's possible explanation - emphasis ours:

Most of the tech experts I've heard from believe the same as I do - that NAND mirroring is likely being used to some degree to brute force the pin on the device. This is where the NAND chip is typically desoldered, dumped into a file (likely by a chip reader/programmer, which is like a cd burner for chips), and then copied so that if the device begins to wipe or delay after five or ten tries, they can just re-write the original image back to the chip. This technique is kind of like cheating at Super Mario Bros. with a save-game, allowing you to play the same level over and over after you keep dying. Only instead of playing a game, they're trying different pin combinations. It's possible they've also made hardware modifications to their test devices to add a socket, allowing them to quickly switch chips out, or that they're using hardware to simulate this chip so that they don't have to.

On Tuesday, The Guardian reported US officials have "classified" the technique they intend to use, in an attempt to prevent its details being made public. Apple will be keen to discover it so they can patch its security to protect its users - while malicious hackers will also be interested in trying to exploit it.

(Reporting by Tova Cohen; Editing by Elaine Hardcastle)