South Korea’s Financial Services Commission (FSC), the country’s financial regulator, has instructed banks and credit card issuers to carry out sweeping security reviews after a wave of cyberattacks struck Shinhan Bank and KB Kookmin Bank, exposing weaknesses in systems that sit outside core banking networks.
According to The Korea Herald, the directive followed an emergency meeting on Friday, led by FSC secretary general Shin Jin-chang, where officials exchanged details of the recent breaches, including how the attacks were carried out, and weighed the sector’s response.
Shin told lenders and card companies to examine every IT system that can be reached from outside their networks. Attackers had targeted less-protected platforms, such as a Shinhan Bank service used by loan agents and a mobile work-support tool for KB Kookmin Bank staff, using artificial intelligence agents.
The scale of the incidents is growing. Shinhan Bank disclosed on Thursday that data on roughly 25,000 customers was compromised after code linked to its communications infrastructure was hacked.
An internal review at KB Kookmin Bank found that details on more than 100 customers had been exposed through an outside intrusion. Industry sources said on Friday that Hana Bank and BNK Busan Bank had also suffered leaks.
Under the FSC’s instructions, firms must map every IT asset and service open to external access and scrutinise vulnerabilities and access controls, whether or not those systems serve customers. They must also reduce the volume of information visible externally, close any pathway that lets users reach internal data without authentication, and make sure authentication is enforced whenever internal information is accessed.
The regulator plans to gather the results quickly and use them to shape new measures to reinforce cyber defences across the financial industry. To support the reviews, authorities will issue a cybersecurity checklist for firms to complete and return.
The FSC acts as South Korea’s financial regulator. The press release does not provide further detail on its wider remit.
Alongside the checks, the FSC, Financial Supervisory Service and Financial Security Institute have opened on-site inspections into the attacks, with staff sent to all four affected banks.
Threat data, including attacker IP addresses, attack techniques and attempted intrusions, is being passed to the Korea Internet & Security Agency, other authorities and financial firms so the response can be coordinated. Regulators will also supervise the affected banks to make sure customers are protected and reimbursed for any losses.
Officials said the urgency stems from the need to establish quickly what data was taken and how, in order to calm public concern. Shin urged firms to be thorough “so that the public does not feel anxious,” according to officials.
A financial industry official said, “People will only feel reassured once it is confirmed that the leaked information was not directly related to their financial transactions. That is why financial companies were urged to conduct thorough checks.”
FSC secretary general Shin Jin-chang said, “We will closely monitor cyberthreats targeting the financial sector and work closely with relevant parties by sharing threat intelligence promptly. We will thoroughly analyze the causes and methods of the attacks and swiftly develop measures to strengthen the system.”
Copyright © 2026 FinTech Global
