Kevin David Mitnick, the social engineer, hacker and cybersecurity trailblazer died last week aged 59.

Mitnick, who was described as a ‘computer terrorist’ by the US Justice Department during their hunt for him in the early 1990s, served two jail sentences for breaching computer systems in 1988 and 1999 before becoming a high profile cybersecurity expert.

In his biography, Mitnick described his curiosity as a driving force, saying: “All of this was really to satisfy my own curiosity, see what I could do, and find out secret information about operating systems, cell phones, and anything else that stirred my curiosity.”

His lifetime obsession with exploring systems and technology started with him figuring out the paper transfer systems on the 1970s Los Angeles transit network and his understanding of social engineering was established with his coaxing where to buy the required ticket punch from a friendly bus driver.

During his high school years he went on to break into the DEC computer systems and, like many other hackers before him, exploit the analogue telephone network through whistles and tones.

His convictions came after his breaking into bigger targets, with his first conviction coming after copying DEC’s software and his period on the run after breaching parole and breaking into AT&T’s voicemail system.

During his second stint in prison, he became the focus of the ‘Free Kevin’ movement which was one of the early campaigns of the then nascent world wide web.

The Free Kevin campaign was fuelled by some of the more outlandish claims about his abilities including the assertion he could start a nuclear war through whistling into the NORAD (North American Aerospace Defense) modems.

Following his release after five years in prison, he embarked on a career as a white hat hacker and security consultant.

He also joined the public speaker circuit and visited Australia a number of times, including a 2016 trip where he claimed that, in over 16 years as a penetration tester, he had never failed to breach a system.

In his writing, Mitnick disdained the misuse of the word ‘hacker’, preferring it to be used in its more traditional sense as someone who enjoyed exploring and tinkering with systems.

Mitnick is survived by his wife, Kimberley Mitnick, who is pregnant with their first child. He passed away after a brief battle with pancreatic cancer.