Hackers are often depicted as tech wizards, clad in hoodies instead of robes, who can bypass any firewall in a fury of keystrokes. Often, however, the methods employed by hackers are mundane, to say the least, as are their motives. Most of the hackers on our list wanted nothing more than to see if they could get away with it. (Although at least one breached U.S. defense websites to find out the truth about aliens.)   

Here are seven of the most famous hackers in history. There are other hackers who no doubt deserve a spot on our list, but the best hackers are the ones who can infiltrate a network without leaving a trace; they’re the ones no one has ever heard of.  

1. Kevin Mitnick 

Kevin Mitnick became “the world’s most famous hacker” after stealing computer code from tech companies like Nokia and Motorola. However, his crowning achievement came in 1982 when he hacked into the North American Aerospace Defense Command (NORAD), a stunt that got him on the FBI’s most wanted list and inspired the movie “War Games.” Mitnick was only in it for cheap thrills. Still, that didn’t stop authorities from sentencing him to five years in prison.  

Mitnick employed social engineering, a concept he helped popularize that involves deceiving a user into providing secure information. In the case of Motorola, Mitnick simply called and asked for the security manager’s username and password, and he got it! Today, Mitnick is a renowned white-hat hacker, offering his unique set of skills to companies at risk of cyberattack.   

White, Black, and Grey: Types of Hackers Explained 

When you think of a hacker, you’re probably thinking of a black-hat hacker. These techies find and exploit weaknesses in computer networks for personal or financial gain or simply to cause harm. However, not all hackers are bad.  

White-hat (ethical) hackers work on behalf of organizations to find and address vulnerabilities. Grey-hat hackers perform the same work without advance permission: Imagine a burglar leaving a bill for finding a flaw in your home’s security.   

2. Anonymous 

Anonymous is a collective of online “hacktivists” whose origins can be traced to the early days of 4chan, an anonymous imageboard (hence the name). Members would organize raids of online chatrooms to troll users, but with time, their antics became socially and politically motivated. Recently, the group declared a cyber war against Russia for its invasion of Ukraine. Dozens of hackers with alleged ties to Anonymous have been arrested, but with no real leadership or structure, the group continues to launch cyberattacks on world governments and million-dollar corporations in the name of social justice.  

3. Astra 

Little is known of the hacker who went by the name Astra. In 2002, Astra infiltrated the Dassault Group, a French company with civil and military aviation subsidies, and stole and subsequently sold corporate secrets, including information on weapons systems. Dassault reported damages in excess of $361 million. Astra was arrested in Athens, Greece, in 2008. Greek authorities have yet to release his name to the public but describe him as “a 58-year-old mathematician.” 

4. Gary McKinnon 

Gary McKinnon committed “the biggest military computer hack of all time” when, between February 2001 and March 2002, he accessed NASA and other defense websites, disrupting supply lines, causing $700,000 in damage, and leaving notes like “Your security is crap.” His reason? Aliens. McKinnon claims he was searching for evidence of UFOs. McKinnon, a London resident, was to be extradited from the U.K. to the U.S., but then-Home-Secretary Theresa May blocked the extradition, declaring that it would infringe upon his human rights. 

5. Steve Wozniak 

Steve Wozniak, “the Woz,” is known for cofounding Apple, but his first foray into business involved an illegal phone-hacking circuit board. In the fall of 1971, Wozniak happened upon Ron Rosenbaum’s “Secrets of the Little Blue Box,” an article about devices that generate the tones needed to trick telephone networks into making long-distance calls for free.  

Wozniak and then-high-school-senior Steve Jobs got to work building a blue box of their own. After making a working model, they went dorm to dorm selling copies to fellow students at Berkeley. (Wozniak was expelled from the University of Colorado Boulder for hacking into the school’s network.) Creating a blue box gave the two Steves enough confidence to build something a little more ambitious. “If we wouldn’t have made blue boxes, there would have been no Apple,” said Jobs. 

6. Gummo 

Gummo’s story went viral after he sat down for an interview on the YouTube channel Soft White Underbelly. He shared how computers helped him cope with a troubled childhood, including the loss of his mother, and how hacking offered the means to survive. After creating and selling software that hacked DirecTV, Gummo was arrested and offered a choice: go to prison or lend his expertise as a consultant. He chose the latter. After paying off his debt to society, Gummo did consulting work that led to him setting up networks used by the Chicago Mercantile Exchange (CME) and the New York Stock Exchange (NYSE).  

Despite claiming to have over $7 billion in Bitcoin stashed away, Gummo works 9 to 5 protecting organizations and individuals as a white-hat hacker. “Knowing that I’m preventing someone’s grandmother from being a victim of some sort of cyber extortion scheme,” he said, “that’s the thing I get up for each day.” 

7. Adrian Lamo 

Adrian Lamo is a grey-hat hacker through and through. Known as the “Homeless Hacker,” Lamo would travel around the country by Greyhound bus, hacking into corporations like AOL, Yahoo, and The New York Times and offering to fix their security vulnerabilities for free before notifying the media of his escapades. He did this not to cause harm but to prove how dangerous the internet could be for anyone who left themselves vulnerable.  

In the case of the Times, Lamo accessed their internal server in 2002 and added himself to their list of op-ed contributors. He was later caught and sentenced to six months of house arrest. Hacking one of the nation’s largest newspapers has its consequences, but in Lamo’s defense, he was only able to gain access because some Times employees were using their Social Security numbers as passwords.  

Sources: 
https://www.mitnicksecurity.com/about-kevin-mitnick-mitnick-security
https://us.norton.com/blog/emerging-threats/black-white-and-gray-hat-hackers
https://www.cnbc.com/2022/03/25/what-is-anonymous-the-group-went-from-4chan-to-cyberattacks-on-russia.html
https://abcnews.go.com/International/story?id=1945581&page=1
https://www.theguardian.com/world/2012/oct/16/gary-mckinnon-hacker-sparked-storm
https://www.theatlantic.com/technology/archive/2013/02/the-definitive-story-of-steve-wozniak-steve-jobs-and-phone-phreaking/273331/
https://www.wired.com/2010/05/lamo/