The network of the financial IT solution provider Koscom was found to have been penetrated amid escalating concerns over the recent credit card leak.

“Considering that Koscom boasts a relatively stable system, it is worrying for the overall security business’ data management and security,” said an official who declined to be named.

Koscom manages customer information for 35 of the 62 domestic security companies, including details of customers’ account numbers, transaction records and accounting.

According to financial sources Wednesday, the hacking of the financial IT solution provider comes as a shock with the domestic market depending on Koscom for its IT infrastructure.

A hacking incident in February 2012 led Koscom to step up its security levels by separating computers for Internet use from another containing company data and without a Internet connection.

One staff member, however, simply transferred company data with a USB stick to a different computer, which in turn was infected with a malicious code that even extends to Japan. The company said the data spill was limited to the staff member’s computer, assuring that their internal network was safe.

Online security systems have been regularly penetrated, notably in an earlier hacking incident at Leading Investment and Securities Co. in May 2011. Financial sources said customers’ personal information was at risk despite upgrades in security measures.

By Yoon Ha-youn, Intern reporter (yhayoun@heraldcorp.com)