KEY POINTS:
A Whitianga teenager with no formal computer training has confessed to cyber crime which has surprised international investigators with its sophistication.
Owen Thor Walker, who taught himself computer programming and encryption, was allegedly the mastermind of a "botnet" coding group said to have infected a million computers and caused millions of dollars of damage.
In Thames District Court today, the unremarkable-looking teenager pleaded guilty through his lawyer, Tony Balme, to six charges between January 30, 2006 and November 28, 2007, when he was aged 17 and 18 years.
According to police, Walker - known on-line as "Akill" - received just under $40,000 for his part in the attacks, which included a global adware scheme and the collapse of a computer server at the University of Pennsylvania.
At his brief appearance in the dock before Judge Arthur Tompkins, Walker showed no emotion, his below-shoulder-length fair hair framing a thin, pale face.
His parents looked on from the small public gallery as the judge convicted the 18-year-old and remanded him on continued bail until May 28 for sentencing.
Outside, Walker had donned sunglasses and a black jacket, the hood of which he pulled closely around his face. He was hurriedly escorted away from the courthouse by his mother and lawyer.
Judge Tompkins ordered pre-sentence and reparation reports. He did not require police prosecutor Sergeant Mark Wickham of Hamilton to outline any evidence, saying he would take it "as read".
According to a copy of the 15-page summary of facts given to NZPA afterward, the offending falls within four categories:
* The creation and possession of computer software enabling unauthorised access to computer systems;
* The unauthorised installation of malicious computer software onto computer servers, computer networks or individual computers;
* Using the unauthorised computer access to obtain a pecuniary advantage;
* Using unauthorised computer access to damage or interfere with computer systems - the most serious of the charges against Walker, which carries a maximum penalty of seven years' imprisonment.
The quiet, fresh faced computer whiz kid suffers from Asperger's syndrome, a mild form of autism often characterised by social isolation but great intelligence and talent in a particular area.
He was reportedly bullied at school and left in Year 9 to study by correspondence.
Walker started experimenting with bot programmes and created his own code, continually developing, redesigning and adding to it.
International cyber crime investigators considered Walker's to be "amongst the most advanced bot programming" they had encountered, says the prosecution summary.
His bot code contained a number of special features that protected it from discovery, allowing it to spread automatically and identify and destroy rival bot code.
One feature automatically disabled any anti-virus software on an infected computer and prevented the software from being updated.
Walker, also identified on line as "Snow Whyte" and "Snow Walker," set up the command and control of his botnet using computer servers outside New Zealand, mainly in Malaysia. He either leased server space or accessed servers illegally.
Prosecutors say the exact number of computers in which his bot code was installed may never be known, but it was tens of thousands.
When interviewed, Walker explained how his bot code included a function that allowed him to operate through another, randomly chosen computer as a proxy, making it harder to trace back to him.
Law enforcers' interest in the solitary teen at remote Whitianga was triggered when a Distributed Denial of Service (DDoS) attack caused a computer server at the University of Pennsylvania to fail in February 2006.
The FBI began an investigation, honing in on a Pennsylvania student - presently facing criminal prosecution in the US - who had connections to "Akill".
Eventually, with the help of New Zealand police, the screen name was traced to Walker.
He was also linked with a cyber crime investigation conducted in the Netherlands, where botnets were being used to covertly install adware on computers.
Netherlands authorities established that the New Zealander was responsible for 1.3 million illegal installations of adware.
His total income from this activity has been assessed at $36,174.65.
Walker admitted that although he knew what he was doing was illegal, he had not considered it to be criminal.
According to the summary of facts, the police officer who interviewed the youth "formed the view that his interest in computer gaming had spilled over into the real world".
- NZPA