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The 4 most notorious hackers

From Snowden to Mitnick, we trace the lives of those who hack

Edward Snowden picture

Unlike white hat or ethical hackers, who hack to help find flaws and vulnerabilities and fix them to protect organizations and governments, black hat hackers are in it for the money. Black hat hacking costs consumers and companies trillions of dollars every year. 

Whatever black hat hackers’ motivation is, they leave a trail of computational carnage and victims in their wake. Here, we investigate the world’s most notorious hackers, who they were, what they did, and what happened to them.

1. Kevin Mitnick

Possibly the most well-known hacker of all time is Kevin Mitnick. In fact, the Department of Justice called him the "most wanted computer criminal in US history." He was also one of the FBI’s Most Wanted after hacking into 40 major corporations. 

His high-profile 1995 arrest and five years in prison for various cyber crimes brought him into the mainstream just as the internet took off. 

In 1999, as part of a deal, he pled guilty to four counts of wire fraud, two counts of computer fraud and one count of illegally intercepting communications.

Since then, he has become a highly sought-after security consultant to many large corporations, organizations, and governments worldwide. That means he now gets paid lots of money doing the kind of thing he went to prison for.

2. Edward Snowden

While he did not use hacking tools, Edward Snowden used social engineering techniques and lax security policies to rifle through the National Security Agency’s (NSA) servers and 20,000 documents without leaving a trace. 

Employed as a system administrator for the NSA, Snowden had access to top-secret documents, and no one was auditing systems for leaks. With the privileges of a system administrator, Snowden could look for any file he wanted, pop it onto a memory stick, and leave. 

He later flew to Hong Kong to meet Guardian journalist Glenn Greenwald and filmmaker Laura Poitras. Revelations about US security started appearing in the Guardian and Washington Post in the following weeks. 

Snowden fled to Russia and claimed political asylum. 

3. Graham Ivan Clark

This teen hacker orchestrated one of the summer 2020 Twitter hacks. He and two others used social engineering and other techniques to access the social media giant’s internal systems. They proceeded to use 130 celebrities’ accounts to make more than $100,000 in a cryptocurrency scam.

Among the celebrities whose accounts were taken over were President Joe Biden, former President Barack Obama, Elon Musk, Kanye West, Bill Gates, Jeff Bezos, Mike Bloomberg, Warren Buffet, Floyd Mayweather, Kim Kardashian, Apple, Uber, and other companies.

As part of a plea deal, Clark will spend three years in prison and be banned from using computers without permission and supervision from law enforcement.

4. Adrian Lamo

Also known as the “Homeless Hacker,” Lamo broke into the networks of The New York Times, Google, Yahoo!, and Microsoft before his 2003 arrest. He got his nickname because he hacked companies from coffee shops and libraries and lived in abandoned buildings or on friend’s couches. 

In 2004, Lamo pled guilty to one felony count of computer crimes against the Times, LexisNexis, and Microsoft. For that, he received six months’ detention and two years’ probation.

In 2010, Chelsea Manning, an army private then known as Bradley Manning, contacted Lamo via instant message. Manning told Lamo about the leak of a classified video of a helicopter attack in Baghdad that killed 12 people to Wikileaks. Lamo then reported the theft to the FBI. 

Lamo died in 2018 at 37 years old. According to the coroner's report, Lamo’s bloodstream contained a range of prescription drugs at the time of death. Lamo’s death was ruled an accident, according to an NPR report.

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