Kevin Mitnick, Once the ‘Most Wanted Computer Outlaw,’ Dies at 59

Kevin Mitnick, who at the dawn of widespread internet usage in the mid-1990s became the nation’s archetypal computer hacker — obsessive but clever, shy but mischievous and threatening to an uncertain degree — and who later used his skills to become “chief hacking officer” of a cybersecurity firm, died on Sunday in Pittsburgh. He was 59.

Kathy Wattman, a spokeswoman for the cybersecurity company he partly owned, KnowBe4, said the cause was pancreatic cancer.

Described by The New York Times in 1995 as “the nation’s most wanted computer outlaw,” Mr. Mitnick was a fugitive for more than two years.

He was sought for gaining illegal access to about 20,000 credit card numbers, including some belonging to Silicon Valley moguls; causing millions of dollars in damage to corporate computer operations; and stealing software used for maintaining the privacy of wireless calls and handling billing information.

Ultimately, he was caught and spent five years in prison. Yet no evidence emerged that Mr. Mitnick used the files he had stolen for financial gain. He would later defend his…