Everybody and their brother has been reporting for weeks that the Israel-based firm Cellebrite assisted the Federal Bureau of Investigation with unlocking the iPhone used by Syed Farook, one of two shooters who killed 14 people in San Bernardino County in December. But The Washington Post says otherwise: the bureau paid so-called "gray hat" hackers for the undisclosed zero-day software exploit.

The Post cites anonymous sources, and Ars could not immediately verify the report. The outlet says the undisclosed hackers who assisted the FBI are "ethically murky" because they are somewhere in between "white hats" who disclose their exploits to companies so they can be fixed, and "black hats" who are in the business of stealing private data.

"The individuals who helped the FBI in the San Bernardino, California, case fall into a third category, often considered ethically murky: researchers who sell flaws to governments, companies that make surveillance tools, or groups on the black market," the Post reported Wednesday.

Apple said last week it would not ask the FBI how it cracked the iPhone, and Ars has reported that the gadget maker has few legal legs to stand on if it wants the government to cough up the recipe the authorities managed to acquire. Gray hats are like mercenary soldiers and have no allegiance. And the longer their exploits remain secret, the longer the hackers can financially capitalize off of them.

Farook's iPhone has been at the center of a bitter dispute between Apple and the FBI, but that legal battle—in which a judge had ordered Apple to write code to assist the authorities in unlocking the phone—came to an abrupt halt last month. The government suddenly said it "successfully accessed the data" on the phone without Apple's assistance. FBI Director James Comey said recently that the government purchased the hack and that it was only successful on the 5C running iOS 9.

The government, meanwhile, is pressing a different case in a New York courtroom to get Apple to assist in unlocking a drug dealer's iPhone 5S.