Regarding unauthorized relaying of external emails by the email relay system managed by our company (second report)

＞Please check here for the first report.
＞Please check here for the third report.
＞Please check here for the final report.

SB Technology has discovered that the email relay system of Local Government Information Security Cloud, which our company built and manages, became in a state where unauthorized relaying (open relay) was possible due to a setting change during troubleshooting maintenance. We have confirmed that the email was used for transmission, and are continuing to investigate this incident.

As announced on March 21, 2022, 912,299 fraudulent emails were sent by a malicious third party. As a result of the investigation so far, we have determined the total number of emails sent from 5 prefectures and 8 cities that were spoofed as the sender of fraudulent emails (both to domestic domains (.jp) and others), and 15 types of emails sent by unauthorized relay. We would like to inform you that we are now able to report on the subject.
We deeply apologize for the great concern and inconvenience this incident has caused to our customers and other stakeholders.

If you received a suspicious email with the subject below on March 18, 2022, please do not click on the link or open the attachment if there is a link or attachment in the email message. Please delete all of them. Additionally, if you have any concerns that may fall under this issue, please contact us.

The following items have been confirmed so far:

1. Breakdown of the number of emails sent by city that were spoofed as the sender of fraudulent emails (in order of prefecture number)

2. Subject lines of 15 types of emails sent by unauthorized relays