The 21 year-old college student charged with hacking former Alaska Governor Sarah Palin's Yahoo email account was using a compromised computer that was secretly logging and reporting information without his knowledge, his lawyers say.
In court filings attorneys for David Kernell say that the Acer notebooks that US Federal Bureau of Investigation agents seized from Kernell's Knoxville, Tennessee, apartment last year apparently contained spyware.
"The program, which was installed by an unknown method before the computer ever came into Mr Kernell's possession, uses sophisticated technology to record and report personal information without the user's knowledge," his attorneys state, in a November 30 motion.
Although the court documents do not identify the program, they indicate that the software was reverse-engineered and analysed within the five forensic reports the US government produced for this case. Those reports have been filed under seal because they contain personal information.
Kernell is facing a possible five-year prison sentence on a one-count felony computer hacking charge. Prosecutors say that he accessed Palin's personal email account in September 2008, while she was running as a vice-presidential candidate, and used Yahoo's password reset feature to gain access to her mail. The emails were posted online and an anonymous member of the 4chan discussion board named Rubico claimed responsibility for the act.
In her recent autobiography, Palin described the incident as the "most disruptive and discouraging" event of her losing 2008 campaign.
It's not uncommon for computers to be infected with malicious software that logs personal information, said Paul Ferguson a security researcher with antivirus vendor Trend Micro. In fact, he guesses that one in five PCs have some sort of malicious program on them, giving backdoor access to cyber-criminals.
David Kernell is the son of Democratic Tennessee state representative Mike Kernell. His trial is set to begin on April 20.