A Seoul court on Monday sentenced a habitual hacker in his 40s to a one-year jail term for stealing and illicitly trading the personal information of more than 100,000 people.

The culprit, surnamed Shin, was found to have hacked the private information of about 29,000 customers of the Internet portal Daum Communications through a desktop computer in the Philippines in September 2007.

The information included Daum customers’ names, resident registration numbers, phone numbers and copies of identification cards, according to the Seoul Central District Court.

Shin blackmailed the portal operator for 5 million won ($4,900) in return for not releasing the stolen data. But he released the information to another person for 1 million won.

The total number of stolen identities came to 108,000 including the cases at Daum and nine other local websites.

In addition, Shin extorted 7 million won from executives of Mr. Pizza after stealing customers’ data in May 2008.

The verdict said that “Shin’s crime was very serious as he sold the data as well as hacking them by penetrating a variety of Internet sites.”

It also stressed that Shin committed another crime after being subject to criminal punishment for similar misdeeds.

Shin was sentenced to a prison term of one year and six months for hacking the data of 1.75 million customers of Hyundai Capital in 2011.

Hyundai Capital at the time revealed that not just basic personal data ― such as residential registration numbers and mobile phone numbers ― but also key financial data required to make financial transactions, such as passwords to loan services, had been taken by the hacker.

By Kim Yon-se (kys@heraldcorp.com)