Niconico, the Japanese video-sharing website, and its parent company KADOKAWA Inc. have provided crucial updates regarding the significant cyberattack they experienced earlier in June 2024. The Niconico cyberattack, identified as a ransomware assault, has raised substantial concerns about data security and user privacy. Here’s a comprehensive look at the current situation after the cyberattack on Niconico, including the steps taken by the companies, the nature of the leaked information, and recommendations for users.

Niconico Cyberattack: Incident Overview

Niconico and KADOKAWA Inc. discovered the ransomware attack on their data center servers and immediately initiated a response plan. A specialized task force, along with external cybersecurity experts, was deployed to investigate the Niconico cyberattack and assess the extent of the data compromise. The attackers claimed to have exfiltrated sensitive information, a claim which has been substantiated by the initial findings of the investigation. [caption id="attachment_79668" align="aligncenter" width="631"] Source: Niconico X account[/caption] The data breach affected various types of information held by Niconico and KADOKAWA Inc. Notably, the Niconico data breach included:

1. Business Partner Information: This includes contracts, quotations, and other documents related to business dealings.
2. Personal Information of Creators: Creators using music monetization services (NRC) were impacted, with their personal details being leaked.
3. Employee Information: Personal data of all employees, including contract employees, temporary workers, part-time staff, and even some retired employees of Dwango Inc., were compromised.
4. Internal Documents: Various internal documents, potentially containing sensitive operational details, were also accessed.

Password Security and Credit Card Information

Niconico has assured its users that account passwords are stored in an encrypted format using cryptographically secure methods known as hashing. This measure significantly reduces the risk of passwords being immediately misused if they are leaked. However, Niconico advises users to change their passwords, especially if they use the same password across multiple services. Importantly, Niconico has confirmed that no credit card information was compromised during the attack. The company does not store such data within its systems, thus eliminating the risk of credit card information leakage.

Immediate Actions and Recommendations

In light of the breach, Niconico and KADOKAWA Inc. have taken several critical steps:

1. Task Force Deployment: A specialized team was formed to handle the situation, investigate the breach, and mitigate further risks.
2. External Investigation: External cybersecurity agencies have been engaged to conduct a thorough investigation, the results of which are expected by the end of July 2024.
3. Law Enforcement Collaboration: The companies have reported the incident to the police and relevant authorities and are cooperating fully with ongoing investigations.
4. User Notifications: Individual notices and apologies are being sent to all affected parties, including external creators, business partners, and former employees. For those who cannot be contacted individually, the public announcement serves as a notification.

Precautionary Measures for Users

Given the potential for personal information misuse, Niconico and KADOKAWA Inc. urge users to be vigilant against phishing attempts and other suspicious activities. Users are advised to:

1. Change Passwords: Update passwords for their Niconico accounts and any other services where the same password might be used.
2. Monitor Communications: Be cautious of unsolicited emails, especially those requesting personal information or directing to unfamiliar websites.
3. Report Suspicious Activity: Utilize the dedicated contact point set up by Niconico for inquiries and to report any suspicious activities or potential breaches related to this incident.

Both Niconico and KADOKAWA Inc. have expressed deep regret over the inconvenience and distress caused by this incident. Niconico and KADOKAWA Inc. sincerely apologized for the inconvenience and concern resulting from the cyberattack on Niconico, and expressed gratitude for the patience and understanding shown by all those affected during that challenging period.