// CONFIRMED RANSOMWARE ATTACKS · COUNTRY
Ransomnews has confirmed 367 ransomware attacks in Japan between October 2018 and August 2026, each one verified against a public source such as a breach notification, regulatory filing, court record or press report. That is 3.9% of the 9,520 confirmed incidents in the dataset. So far in 2026, 77 have been confirmed, against 93 in 2025 and 100 in 2024. The most affected sector is manufacturing, with 118 confirmed victims (32%). Tokyo is the city with the most confirmed victims, at 126. Where the operator is attributed, LockBit leads with 25 confirmed victims. A ransom payment is on the public record in 1 case and a refusal in 27; the outcome is unrecorded in the remaining 339.
Confirmed ransomware attacks in Japan by year
The current year is a partial count. Confirmation lags the attack itself, so recent months keep filling in after the fact; read a low figure for the latest year as incomplete rather than as a decline.
| Year | Confirmed attacks | Ransom paid (public) | Ransom refused (public) |
|---|---|---|---|
| 2018 | 1 | 0 | 0 |
| 2019 | 1 | 0 | 0 |
| 2020 | 8 | 0 | 1 |
| 2021 | 14 | 0 | 4 |
| 2022 | 25 | 0 | 2 |
| 2023 | 48 | 0 | 6 |
| 2024 | 100 | 1 | 7 |
| 2025 | 93 | 0 | 5 |
| 2026 (year to date) | 77 | 0 | 2 |
Which ransomware groups attack organisations in Japan most
The operator is attributed in 152 of the 367 confirmed incidents. Counts are confirmed victims, not leak-site claims, so they run well below the totals the groups publish about themselves. Group names link to the live Ransomtracker profile where one exists.
Most active groups by confirmed victims
Where the confirmed attacks in Japan fall
Most affected sectors
Cities with the most confirmed victims
Ransom payment outcomes in Japan
Among the 28 confirmed incidents in Japan where the outcome is on the public record, 1 paid and 27 refused, a disclosed payment rate of 3.6%. The remaining 339 carry no public statement either way. Victims that pay have every incentive to stay quiet and public bodies are the most likely to announce a refusal, so treat this as the disclosed rate, not the true one. The ransomware payment rate analysis explains how the disclosed rate has moved since 2018 and how it compares with incident-response firm samples.
Largest confirmed ransomware attacks in Japan by records exposed
Record counts are recorded only where a named source disclosed them, which is the minority of cases, so this table ranks disclosed impact rather than true impact.
| Date | Organisation | Sector | Location | Records | Group | Ransom paid | Source |
|---|---|---|---|---|---|---|---|
| February 2024 | Izumi Co., Ltd. | Retail | Hiroshima, Japan | 7,784,999 | — | Unknown | izumi.co.jp |
| September 2025 | Asahi Group Holdings | Food and Beverage | Tokyo, Japan | 2,289,000 | Qilin | No | asahigroup-holdings.com |
| January 2025 | Sanrio Entertainment Co., Ltd. | Other | Tokyo, Japan | 2,000,000 | — | Unknown | scan.netsecurity.ne.jp |
| June 2023 | Kokuyo Co., Ltd. | Manufacturing | Osaka, Japan | 1,860,000 | — | Unknown | kokuyo.co.jp |
| August 2025 | Huis Ten Bosch Co., Ltd. | Other | Sasebo, Japan | 1,546,000 | — | Unknown | english.huistenbosch.co.jp |
| February 2025 | Newton Financial Consulting, Inc. | Finance | Shinjuku, Japan | 1,300,000 | — | Unknown | newton-fc.com |
| March 2026 | Nippon Telenet Co., Ltd. | Utilities | Kyoto, Japan | 1,041,044 | — | Unknown | nippon-tele.net |
| January 2024 | Saitama Prefectural Health Promotion Foundation | Healthcare | Saitama, Japan | 940,000 | — | Unknown | saitama-kenkou.or.jp |
| May 2024 | Iseto Co., Ltd. | Service | Kyoto, Japan | 900,000 | 8Base | Unknown | asahi.com |
| April 2026 | YCC Information Systems Co., Ltd. | Technology | Yamagata, Japan | 754,508 | — | Unknown | yamagata-ycc.co.jp |
Most recent confirmed ransomware attacks in Japan
The 25 most recently confirmed of 367 incidents, newest first. Every row links to the public source it was verified against.
| Date | Organisation | Sector | Location | Records | Group | Ransom paid | Source |
|---|---|---|---|---|---|---|---|
| August 2026 | Ambition DX Holdings Co., Ltd. | Technology | Tokyo, Japan | — | SETTRA | Unknown | ssl4.eir-parts.net |
| August 2026 | Akatake Engineering Co., Ltd. | Manufacturing | Numazu, Japan | — | The Gentlemen | Unknown | akatake.co.jp |
| August 2026 | Daisen Co., Ltd. | Manufacturing | Toyohashi, Japan | — | AiLock | Unknown | daisen.co.jp |
| August 2026 | REXT Co., Ltd. | Retail | Tokyo, Japan | — | — | Unknown | rext.jp |
| August 2026 | CEC Co., Ltd. | Technology | Tokyo, Japan | — | — | Unknown | cec-ltd.co.jp |
| July 2026 | Solid Advance Co., Ltd. | Technology | Tokyo, Japan | — | AiLock | Unknown | solid-adv.co.jp |
| July 2026 | Nichirei Corporation | Food and Beverage | Tokyo, Japan | — | RansomHouse | Unknown | nichirei.co.jp |
| July 2026 | Kaneko Agricultural Machinery Co., Ltd. | Manufacturing | Hanyu, Japan | — | — | Unknown | kanekokk.co.jp |
| July 2026 | Nihon Kotsu Co., Ltd. | Transportation | Tokyo, Japan | — | AiLock | Unknown | nihon-kotsu.co.jp |
| July 2026 | Network Japan Co., Ltd. | Service | Niigata, Japan | — | — | Unknown | happiness-to-everyone.com |
| July 2026 | Hachioji Junior & Senior High School | Education | Tokyo, Japan | — | — | Unknown | hachioji.ed.jp |
| June 2026 | Koyasan University | Education | Koya, Japan | — | — | Unknown | koyasan-u.ac.jp |
| June 2026 | Meitetsu Kyosho Co., Ltd. | Other | Nagoya, Japan | 4,000 | — | Unknown | mkyosho.co.jp |
| June 2026 | Higuchi Inc. (subsidiary) | Retail | Tokyo, Japan | — | Stormous | Unknown | higuchi-inc.co.jp |
| June 2026 | Japan Local Character Association | Government | Hikone, Japan | — | — | Unknown | gotouchi-chara.jp |
| June 2026 | Musashino University | Education | Tokyo, Japan | — | Qilin | No | newsdig.tbs.co.jp |
| June 2026 | Faith Group | Manufacturing | Osaka, Japan | — | — | Unknown | faith-gr.co.jp |
| June 2026 | D&M Co., Ltd. | Manufacturing | Tokyo, Japan | 633 | — | Unknown | rext.jp |
| June 2026 | Shokusou Co., Ltd. | Food and Beverage | Obihiro, Japan | — | — | Unknown | shokusou.co.jp |
| May 2026 | Kyushu University | Education | Fukuoka, Japan | 43 | — | Unknown | kyushu-u.ac.jp |
| May 2026 | Chuoh Pack Industry Co., Ltd. | Manufacturing | Kiyosu, Japan | — | — | Unknown | mcpack.co.jp |
| May 2026 | Koa Glass Co., Ltd. | Manufacturing | Tokyo, Japan | — | The Gentlemen | Unknown | koaglass.co.jp |
| May 2026 | Matsuzawa Shoten Co., Ltd. | Retail | Tokyo, Japan | — | SafePay | Unknown | corp.musenet.co.jp |
| May 2026 | CKC Network, Inc. and Gakusan Co., Ltd. | Education | Nagoya, Japan | 664,000 | — | Unknown | ckc.co.jp |
| May 2026 | Aoyama Zaisan Networks Co., Ltd. (Japan Asset Research Institute Co., Ltd., Nitto Real Estate Co., Ltd.) | Service | Tokyo, Japan | — | SafePay | Unknown | azn.co.jp |
Frequently asked questions
How many ransomware attacks in Japan have been confirmed?
Ransomnews has confirmed 367 ransomware attacks in Japan since October 2018, including 77 so far in 2026. Each one is verified against a public source such as a breach notification, regulatory filing or press report. The true total is higher, because many victims never disclose; confirmed counts are a floor, not a ceiling.
Which ransomware group is most active in Japan?
LockBit, with 25 confirmed victims, followed by Qilin (17) and The Gentlemen (10). These are confirmed victims, not leak-site claims, counted among the 152 incidents where the operator is attributed.
Which sector is hit most by ransomware in Japan?
Manufacturing, with 118 confirmed incidents (32% of the total). Service follows with 35, then Technology with 34.
Which cities in Japan have the most confirmed ransomware attacks?
Tokyo (126), Osaka (45), Nagoya (16), Saitama (8), Fukuoka (6). City is recorded where the victim organisation is headquartered or the incident was reported, so distributed organisations are counted once.
How often do ransomware victims in Japan pay the ransom?
Among the 28 confirmed incidents in Japan with a public outcome, 1 paid and 27 refused, a disclosed payment rate of 3.6%. Most victims never state whether they paid, and those who pay have the least reason to say so, so the disclosed rate understates real payment behaviour. The payment rate analysis tracks this figure since 2018.
What is the largest confirmed Japan ransomware attack by records exposed?
Izumi Co., Ltd. (Hiroshima, Japan, February 2024), with 7,784,999 records exposed according to izumi.co.jp. Record counts exist only where a source disclosed them, so this ranks disclosed impact.
How to read this page. Every incident counted here was verified by Ransomnews against at least one public source. Leak-site listings alone do not qualify, because operators inflate, duplicate and occasionally fabricate claims, so these totals are a defensible floor rather than a full census. Records exposed and ransom outcomes appear only where a named source disclosed them. The page is regenerated from the live database, which refreshes weekly. Cite as: Ransomnews Confirmed Ransomware Attacks Dataset, ransomnews.com, with a link to this page. Bulk access and methodology questions: [email protected]. See also the monthly ransomware statistics and the Ransomtracker.