Was KADOKAWA Corporation hit by ransomware?

KADOKAWA Corporation was listed by the Blacksuit ransomware operation (Japan), and stolen data was published on the group's leak site. Darkfield tracks this disclosure with the original leak post, screenshot and group context.

Who is the Blacksuit ransomware group?

Blacksuit is a ransomware operator tracked by Darkfield. See the full operator dossier for its known victims, sectors targeted, IOCs and leak-site infrastructure.

What data was leaked in the KADOKAWA Corporation breach?

Blacksuit published data attributed to KADOKAWA Corporation. Darkfield captured the leak post and a screenshot of the listing.

Ransomware victim disclosure

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KADOKAWA Corporation

Claimed by Blacksuit · listed 2 years ago

25m

Age

since listed · data leaked

Status timeline

ListedJun 27, 2024
Data leakeddate unknown

At a glance

Group: Blacksuit
Status: Data leaked
Country: Japan
Listed on leak site: Jun 27, 2024

About the victim

AI dossier — public-source company profile

KADOKAWA Corporation is a major Japanese publishing and media conglomerate headquartered in Tokyo. The company publishes novels, manga, light novels, magazines, and produces anime and video game content across multiple imprints and subsidiaries including Dwango and NicoNico (a video streaming platform).

Industry: Publishing & Media

Attack summary

Severity: high — Operational disruption to a major Japanese media conglomerate with significant business impact across multiple subsidiaries and digital platforms (NicoNico is a major video platform). Network-wide encryption of connected infrastructure indicates substantial systems compromise. No exfiltration proof published in excerpt, but operational impact is confirmed.

Blacksuit claims to have gained access to KADOKAWA's network approximately one month before the disclosure and encrypted multiple connected subsidiary networks including Dwango, NicoNico, and the main KADOKAWA infrastructure via compromised hypervisor control points (vSphere/ESXi). No exfiltration is explicitly claimed in the leaked post excerpt.

high

Data the group says was taken

AI dossier — extracted from the leak post

Network-wide encryption across multiple subsidiaries
Corporate infrastructure (vSphere/ESXi systems)
Subsidiary systems (Dwango, NicoNico)

What the group claims

Our team gained access to the Kadokawa network almost a month ago. It took some time, because of the language, to figure out that Kadokawa subsidiaries' networks were connected to each other and to get through all the mess Kadokawa's IT department made there. We have discovered that Kadokawa networks architecture was not organised properly. It was different networks connected to the one big Kadokawas infrastructure being controlled through global control points, such as eSXI and V-sphere. Once we have gained access to the control center we have encrypted the whole network (Dwango, NicoNico, Kadokawa, other subsidiaries).

Sources

Victim sitekadokawa.co.jp
Leak posthttp://weg7sdx54bevnvulapqu6bpzwztryeflq3s23tegbmnhkbpqz637f2yd.onion/?id=0thvgn6ZCK8naXiW

Source

Indexed 2 years ago

This page surfaces a public ransomware disclosure indexed by Darkfield. Original posts come from the operator's own leak site; we cross-check against ransomware.live, RansomLook and RansomWatch where applicable. Share this URL freely.

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Disclosure context

About Blacksuit

Blacksuit is a financially motivated ransomware group that emerged in June 2023, quickly establishing itself as a significant threat with 184 documented victims across multiple sectors. The group's origin and specific affiliations remain largely undocumented in public threat intelligence reports, though their operational patterns suggest they operate as an independent entity rather than a traditional RaaS model. Blacksuit primarily targets organizations through common initial access vectors and employs standard ransomware deployment techniques, though detailed technical analysis of their specific encryption methods and whether they consistently employ double extortion tactics has not been widely published by major security firms. The group has demonstrated a clear preference for targeting business services, healthcare, government, and manufacturing sectors, with their victims predominantly located in English-speaking countries including the United States, United Kingdom, and Canada, as well as Spain and Germany. As of current reporting, Blacksuit remains an active ransomware operation with no publicly documented law enforcement disruptions or significant rebranding efforts. The group has been linked to 184 public disclosures across our corpus. First observed on a leak site on June 12, 2023; most recent post June 2, 2025. The operation is currently inactive.

Also tracked as: black suit.

Timeline of this disclosure

June 27, 2024KADOKAWA Corporation listed by Blacksuiton the group's public leak site

Other recent disclosures by Blacksuit

Blacksuit has been linked to 184 public victims on Darkfield. A sample of the most recent:

See the full Blacksuit dossier →

Sector and geography

Geographically, KADOKAWA Corporation is reported in Japan, a country with 220 ransomware disclosures in our corpus.

If your organisation is affected

A listing by Blacksuit means KADOKAWA Corporation appeared on a ransomware extortion site and data attributed to it has been published. If this is your organisation, or a supplier you depend on, the priority is to confirm the intrusion and contain it before the window to act closes.

Engage your incident-response team and preserve forensic evidence before remediating — do not wipe affected systems first.
Force a password reset and revoke active sessions for exposed accounts; rotate any credentials, API keys or certificates that may have been in the stolen data.
Assess regulatory notification duties (GDPR, NIS2, sector regulators) — many carry a 72-hour reporting clock from awareness.
Report the incident to your national CERT, JPCERT/CC (Japan), as required for your jurisdiction.
Monitor for the data appearing on Blacksuit's leak site and across paste and breach channels, and brief downstream partners who may be exposed through you.

How we know this. Darkfield monitors public ransomware leak sites continuously, archiving every new disclosure and the data later released against the victim. Each entry on this page is sourced from the operator's own publication and cross-checked against complementary OSINT feeds (RansomLook, ransomware.live, RansomWatch). We do not collect or host stolen data — only the metadata, timestamps and screenshots needed to make the public disclosure searchable and accountable. Records here are corrected when the original post is edited, retracted, or merged with another disclosure.