NEWS
1-6-2 Marunouchi, Chiyoda-ku, Tokyo 100-8246 Japan

August 23, 2023

Notification of Data Breach and Possible Leakage of Personal Information
Zeon Corporation

We confirmed that a third party gained unauthorized access to our corporate servers, which may have led to the leakage ofcertain personal information under our control. At this time, there is no evidence that any such information has been subject tounauthorized use, and we are taking every action to minimize any inconvenience or concern for those whose information may
have been affected.
Outline of the Incident
On August 16, 2023, an external attack was detected on the Company and Group servers. We immediately contacted thebusiness that maintains the servers and implemented the necessary countermeasures, including the immediate disconnectionof the equipment from the network. Subsequent investigation with a cybersecurity firm revealed traces of unauthorized accessin our account management system (directory server) and the possibility that some personal information may have been leaked
to external parties. At this time, we have not confirmed any unauthorized access on any other corporate servers. Any subsequentdiscovery of such an incident will be announced on our website.
Details of Personal Information that May Have Been Leaked to External Parties (total of 13,434 records related to (1) to (2)below)(1) Information on customers and business partners registered in the group addresses managed by the Company (8,236addresses)
E-mail addresses and personal names of customers and suppliers and related domains
We will send an e-mail on August 24, 2023 to all those whose personal information may have been leaked to further informthem of this matter. (Anyone who does not receive an e-mail notification can assume that they have not been affected.)
Please note that our account management system (directory server) only contains the e-mail addresses and names of customers
and suppliers and related domains. There is no possibility of any other information being leaked.
(2) Account information of employees of the Company and its Group companies, as well as employees of subcontractors(5,198 accounts)
User IDs issued by the Company and its Group companies
E-mail addresses issued by the Company and its Group companies
Name (in Japanese characters)
Name (in alphabet)Company name
Department name
Organization codeEmployee number
Phone number
Note that any personal information that has been exposed may be misused to distribute spam or conduct phishing via e-mail.
Please take every reasonable precaution.
Our Response(1) Reporting to administrative organs
The report of this incident was submitted to the Personal Information Protection Commission of Japan on August 22, 2023.
(2) Response to all those whose personal information may have been leaked
We will send an e-mail on August 24, 2023 to all those whose personal information may have been leaked to further informthem of this matter.
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1-6-2 Marunouchi, Chiyoda-ku, Tokyo 100-8246 Japan

We take this situation very seriously, and with the assistance of an external cybersecurity firm, we will continue to investigate
how the incident could have occurred, establish even more robust information security, and strive to prevent any recurrence.
We deeply regret any inconvenience and concern this may have caused and will spare no effort to prevent it from happening
again.
For inquiries regarding this matter, please contact:
Zeon Corporation
Secretariat of the Cyber Security Committee
E-mail: Contact-CyberSecurityCommittee@zeon.co.jp

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