Cyberfeed6 › Countries › Japan
22 IT, OT and crypto incidents involving Japan are listed for May to November 2026 (22 IT). The most common kinds are data breach, ransomware, ransomware & extortion. The country is where the affected organizations or users are, not where the attackers are.
Ransomware cases in Japan hit a record 123 in six months
2026-09-10 · Statistics · Nippon.com (Jiji)
The National Police Agency reported a record 123 ransomware cases in January to June 2026, seven more than a year earlier and the highest half-year total since 2020. Of these, 31 involved major companies and nine forced complete business shutdowns; suspicious access attempts rose about 50%.
Breach at booking supplier Amadeus exposes passenger records at Asian airlines
IT October 31, 2026 · Data breach
IT October 27, 2026 · Ransomware & extortion
Capcom ID and Sony So-net breaches expose about 14 million customer records in Japan
IT October 27, 2026 · Data breach
Capcom ID breach exposes 11.7M accounts
IT October 19, 2026 · Data breach · bleepingcomputer.com
Nikkei third breach in a month, 1.8M records
IT October, 2026 · Data breach · bleepingcomputer.com
Ransomware takes down part of Japan's IDCF Cloud, affecting 495 organizations
IT October 7, 2026 · Ransomware & extortion
Burger King Japan app breach, 11M members
IT October 5, 2026 · Data breach · bleepingcomputer.com
Times Car Rental (Japan) 6.6M accounts exposed
IT September 30, 2026 · Data breach · japantimes.co.jp
Keio Japan hospitality and payment systems ransomware
IT September 28, 2026 · Ransomware · bleepingcomputer.com
Japan Digital Agency VPN flaw exposes 246,000 records
IT September 14, 2026 · Data breach · bleepingcomputer.com
Sakura Internet sales system breach, up to 1.36M accounts
IT August 19, 2026 · Data breach · bleepingcomputer.com
CEC Co. (Japan) tech firm ransomware claim
IT August, 2026 · Ransomware · Roundup: Comparitech: ransomware roundup, August 2026
Ambition DX Holdings (Japan), SETTRA ransomware
IT August, 2026 · Ransomware · Roundup: Comparitech: ransomware roundup, August 2026
Akatake Engineering (Japan), The Gentlemen ransomware
IT August, 2026 · Ransomware · Roundup: Comparitech: ransomware roundup, August 2026
Nihon Kotsu taxi operator shuts systems after attack
IT July 13, 2026 · Cyberattack · bleepingcomputer.com
KDDI Japanese telecom breach, up to 12 million people
IT July 8, 2026 · Data breach · bleepingcomputer.com
Nintendo employee survey data stolen via TinyPulse (WebMD unit)
IT June 18, 2026 · Data breach · bleepingcomputer.com
Oriental Diamond (Japan) manufacturer, The Gentlemen ransomware
IT May, 2026 · Ransomware · Roundup: Comparitech: ransomware roundup, May 2026
Koa Glass (Japan) manufacturer, The Gentlemen ransomware
IT May, 2026 · Ransomware · Roundup: Comparitech: ransomware roundup, May 2026
Gakusan (Japan) company ransomware claim
IT May, 2026 · Ransomware · Roundup: Comparitech: ransomware roundup, May 2026
Chuoh Pack Industry packaging maker (Japan) ransomware
IT May, 2026 · Ransomware · Roundup: Comparitech: ransomware roundup, May 2026
CKC Network (Japan) company ransomware claim
IT May, 2026 · Ransomware · Roundup: Comparitech: ransomware roundup, May 2026