Top 10 Most Dangerous Hackers

But Mitnick has since been superseded by McKinnon, who managed to hack into the Pentagon computers and leave the message “Your security is crap”. Between 2001 and 2002 – sensitive times for America – he repeatedly hacked US military and NASA computers from his base in London, deleting files and changing passwords. At one point he caused a 24-hour shutdown and caused munitions trucks to be stopped. He also left an anti-American message: “US foreign policy is akin to Government-sponsored terrorism these days … It was not a mistake that there was a huge security stand down on September 11 last year … I am SOLO. I will continue to disrupt at the highest levels.” He was arrested in 2002 and is currently imprisoned in Britain, although the US continues to request his extradition. A skilled but also very dangerous hacker who was stopped before he managed to cause a military disaster.

The title of “World’s Most Dangerous Hacker” has been much contested. These final two hackers have both been given it at different points but Kevin Mitnick is now a respectable businessman specializing, as so many former hackers do, in improving the security of their clients’ firms. But this reform has come at the end of a 5-year prison sentence, itself stemming from the violation of a previous sentence (Mitnick committed a hack at the end of his supervised release period). He was arrested in 1995 after breaking into the Department of Justice computers and was said to be able to launch nuclear missiles by whistling down a payphone. The claims may have been exaggerated, but it’s easy to see why he was considered the most dangerous man in the world back in the 1990s.

Affiliated with the hacker group LulzSec, Cody Kretsinger is known to his fellow hackers as “Recursion”. He was convicted in 2013 for his part in a 2011 hack on Sony Playstation, where he managed to get 77 million people’s personal data and cause an outage on the network for 24 days. LulzSec has often been accused of being childish and operating with no real motivation other than, as their name suggests, “the lulz”. They don’t often hack for financial gain – none of the 77 million had their identity stolen – and try to prove just how easy it is to get this kind of data. Kretsinger was granted another relatively light sentence, with only a year in prison for his crimes and many of LulzSec are still at large and operating.

Another hacker associated with WikiLeaks, this is a man with a troubled past. Given up for adoption by his parents he ended up in a children’s home and then later living with his heroin-addicted father and assorted other junkies. After such an unsettled childhood, he was encouraged to channel his energies into computing and he is now the American public face of WikiLeaks, a role that has seen him constantly detained and questioned at airports about his political views. He is also the spokesman for Tor technologies, which aid projects like WikiLeaks by diverting e-mails between several different countries. So an e-mail sent in America may go to three different servers before reaching Iraq, securing the location of both parties. Appelbaum has never convicted of hacking and now lives in Berlin but is obviously still considered a threat as he and his partner are apparently spied on as they sleep. Chilling…

One of the earliest known hackers was Robert Tappan Morris, creator of the “Morris Worm” – a virus that is said to have infected around 6,000 computers. He released it while studying at Cornell in 1988, and was apparently attempting to determine the size of the internet. An innocent enough aim, but he had made his worm death-proof and so it kept replicating itself into unwanted places. He was indicted under the Computer Fraud and Abuse Act and was the first person to do so. As with many of these hackers, his sentence was relatively light – probation, community service and a fine – and he went on to found several companies in the computing sphere.

Known as “the Homeless Hacker” because he did his hacking while couch-surfing and living in hostels, Adrian Lamo is something of a troubled character. Ex-girlfriends describe him as controlling, and he has been diagnosed with Asperger’s Syndrome. He may also have been the subject of a restraining order at one point and is so strongly religious that he refuses to give blood samples. All of which may explain his anti-social behavior – hacking into the New York Times website and adding himself to their expert database. It was for this that he was convicted in 2004, and sentenced to six months’ detention at his parents’ house, plus a fine. He also turned the hacking community against each other – after donating to WikiLeaks, he then exposed one of their contributors – a soldier called Bradley Manning, who was leaking confidential military information. Lamo was supported by Kevin Poulsen and together they were called “felons” and “snitchs” but Lamo maintains that Manning was putting lives in danger with his actions. When last heard of, Lamo was in hiding for fear of Manning’s revenge.

A group of hackers rather than a single one, these were the people responsible for “Operation Aurora“, an international and complex hack in 2009 that targeted 34 companies including Google and Yahoo!. The hackers are believed to come from China as part of the Elderwood Gang – a group of hackers based in Beijing. A Shanghai-based group, PLA Unit-61398, were also believed to be involved, in this massive operation. Google were the first to make the attack public, stating on their blog that they had had their intellectual property stolen – it seems that the hackers were after the source code of these internet giants, rather than any personal information although it later emerged that certain gmail accounts had also been hacked. The hackers behind Aurora have never been caught and said to still be actively hacking. The main result of the whole episode was that Google withdrew from China entirely.

A lot of hackers start young and they will only get younger as this generation grows up surrounded by technology. Jonathan James was the poster boy for teenage hackers, gaining his first conviction at the age of 16 for stealing $170m worth of code from NASA. He did this by hacking into the computers of the Defence Threat Reduction Agency and installing a “backdoor” which gave him access to both messages and source code. He was 15 at the time of the offence and 16 when tried, so received only a juvenile sentence. He resolved to put this past behind him but in 2007 his name was mentioned in conjunction with a hack on the TJX department store. Maintaining his innocence but convinced he would go to prison, he committed suicide on May 18th 2008.

Sometimes hackers can appear perfectly innocuous in their day-to-day lives. Take Kevin Poulsen, who is now News Editor for wired.com – a popular and legitimate site favored by geeks. But he was once a black-hat hacker, pulling off such stunts as winning a Porsche 944 S2 from KIIS-FM by hacking their phone lines and guaranteeing he was the 102nd caller. Like other hackers, he has used his powers for the greater good by identifying MySpace users who were looking for child porn. But he also hacked into the FBI computers and ending up serving a 5-year sentence for his crimes. Since his release, he’s concentrated on his writing career not just at wired but also with his book “Kingpin”. A versatile and, it would seem, reformed hacker.

Currently serving a 10-year prison sentence, Jeremy Hammond is the hacker who stole 60,000 credit card numbers and used them to make donations to charity. So quite a nice hacker then? He certainly seems to be broadly on the side of good, attacking neo-nazis and holocaust deniers, but there’s no denying he’s on the wrong side of the law at the same time. One of his biggest achievements was hacking the e-mails of the Stratfor group, who specialize in global intelligence, and publishing 973 of them on the WikiLeaks website. Among the revelations contained in the e-mails were details of Osama bin Laden’s death and plans to incite a revolution in Venezuela. It was shocking stuff, but it was the credit card theft that saw him sent to jail, some say unfairly.