Amid the growing risks of private information being leaked online, financial companies are waging a security campaign to persuade customers to alter their online transaction passwords.

The promoters include major commercial banks, insurance companies and credit card firms. Via their homepages, they recently asked customers to change their “personal identification numbers” as soon as possible.

Among the financial companies are Shinhan Bank, Korea Exchange Bank, Industrial Bank of Korea, Hyundai Card, Hyundai Capital, BC Card, Samsung Life, and Samsung Fire & Marine Insurance.

Their recent actions come after SK Communication found that the private information of 35 million online users had been hacked in July, the country’s worst-ever security breach.

SK Communication’s search engine Nate and social networking site Cyworld were on the receiving end of the hackers’ attack.

Shinhan Bank advised customers on its homepage to change their passwords, or PINs, from those they or she usually use on other sites.

While Woori Bank, Korea Exchange Bank and Industrial Bank of Korea also participated in the move, SC First Bank and Citibank Korea asked their customers to be more cautious in their cyber transactions.

Companies severely hit by cyber attacks in the first half, such as the National Agricultural Cooperative Federation (Nonghyup) and Hyundai Capital, have been more aggressive in requesting the PIN change.

Hyundai Capital and its affiliate Hyundai Card have continued to inform customers of detailed countermeasures to block information leakage.

Credit card issuers including Samsung Card, BC Card, Shinhan Card and Hana-SK Card have become active in warning of growing risks of possible security breaches.

The insurance industry has also joined the move and they include Dongbu Life, Kyobo Life, Mirae Asset Life, and Hyundai Marine & Fire.

The current law states that if a company is responsible for leaking personal information, they may be slapped with up to 100 million won in fines and up to two years of jail time.

Cyworld and Nate users are now talking of a class action suit, but if the past is anything to go by, their chances of winning are slim.

In 2008, when Auction was hacked into, more than 140,000 users signed up to file a suit, but the lawyers walked away with money.

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