Security Incident at Our Company (First Report)

May 20, 2025
Resonac Holdings Corporation

Today, May 20, we would like to report that a security incident occurred involving an external attack on certain servers of Resonac Corporation.
In response, we have established an Emergency Response Headquarters to investigate the scope of the impact and implement recovery measures.
It will take some time to fully understand the extent of the damage, but at present, we would like to provide the following report based on the information we have. We sincerely apologize for the great concern and inconvenience caused to our business partners and other stakeholders.

1. Incident Overview
On Tuesday, May 20th, an external attack on some of our servers was detected, resulting in a ransomware infection. We immediately initiated an investigation with the cooperation of external experts and established an Emergency Response Headquarters to handle the situation swiftly.

2. Current Status and Future Action
As of 3:30 PM, we are taking measures to prevent further damage, including network isolation. Efforts are underway to protect and restore our systems, and we are committed to minimizing any inconvenience to all affected parties.
Regarding the impact on our financial performance, we are currently assessing the situation. If we determine that this incident will have a significant effect on our future business performance, we will promptly make an official announcement.