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How the Kokubu Seikyo Hospital Ransomware Attack Shook Healthcare

Xray image ransomware

Inside the Attack

On February 27, 2024, Kokubu Seikyo Hospital in Japan experienced a severe ransomware attack on its image management server. This incident disrupted the hospital’s operations significantly, affecting both emergency and general outpatient services. By March 4, the electronic medical record and medical accounting systems were back to normal, but the image management server remained compromised, highlighting the extent and impact of the attack.

Initial Detection

The ransomware attack was first identified when the hospital's image management server became non-operational. This critical server, essential for managing and accessing patient imaging records, was rendered inaccessible, directly impacting patient care and administrative processes. The hospital’s response included halting all internet connections to prevent further spread of the malware, a crucial step in containing the attack.

Magnitude of the Hack

The attack on Kokubu Seikyo Hospital underscores the vulnerability of healthcare institutions to ransomware. Some PDF files of medical records stored on the image management server were encrypted, raising concerns about potential personal information leakage. The hospital promptly reported the possibility of such a leak to the Personal Information Protection Commission, adhering to regulatory requirements and demonstrating transparency.

There is no specific information available about the ransom amount demanded in this ransomware attack or whether the hospital paid any ransom. Details about ransom payments are often not publicly disclosed due to security and privacy concerns, which can complicate efforts to understand the full scope of such incidents.

Response from Kokubu Seikyo Hospital

In response to the attack, the hospital identified that a network device allowing remote desktop connections from outside without authentication was the entry point for the ransomware. Additionally, the image management server lacked antivirus software, which facilitated the malware’s operation. These critical security gaps highlight the importance of comprehensive cybersecurity measures in preventing such incidents.

To mitigate the damage and prevent future attacks, the hospital undertook several immediate actions:

  1. Disconnecting all internet connections.
  2. Reporting the incident to relevant authorities.
  3. Planning an overhaul of the hospital's information system security settings.
  4. Reviewing external connection points and ensuring robust security measures.
  5. Checking the operation status of antivirus software across all systems.
  6. Continuing to implement and reinforce security education for hospital staff.

By March 18, 2024, the hospital had temporarily restored the image management server and resumed emergency and general outpatient services. The infection had not spread further, and the hospital, in collaboration with system vendors, continued working towards a full recovery.

Steps to Take in the Event of a Ransomware Attack

When a ransomware attack occurs, it's crucial to act swiftly and methodically to mitigate damage and facilitate recovery. Here are several immediate steps that organizations should follow:

  1. Maintain Composure: It's essential to remain calm to avoid making hasty decisions that could worsen the situation. Clear-headed actions will enable better decision-making during the crisis.

  2. Disconnect the Infected Devices: Immediately disconnect the infected computers or devices from your network to prevent the ransomware from spreading. This step is crucial in containing the malware and limiting its reach within your systems.

  3. Preserve Evidence: Capture a photograph of any ransom note displayed and document all information about the ransomware attack. This includes how it was identified, the type of ransomware, the ransom demand, and any other relevant details. Preserve the encrypted files and ransom notes as they can be crucial for the investigation.

  4. Assess the Damage: Determine the extent of the infection and identify which systems have been compromised. Understanding the scope of the attack helps in formulating a targeted response strategy.

  5. Contact Authorities: Report the incident to your local law enforcement agency and, if applicable, your country’s cybercrime reporting center. In the U.S., contact your local FBI office. This step ensures that the authorities are aware of the attack and can provide guidance or support.

  6. Notify and Report: If personal data has been compromised, notify the affected individuals and, if required, the relevant data protection authorities. Transparency with stakeholders helps maintain trust and comply with legal obligations.

  7. Engage Cybersecurity Professionals: If you lack in-house expertise, engage a cybersecurity firm like Gftd Japan to assist with the response and recovery process. Professional help can be invaluable in effectively managing and mitigating the incident.

  8. Backup Encrypted Files Before Any Recovery Attempts: Before attempting any recovery, ensure that you backup the encrypted files. This step is vital to prevent data loss during the recovery process.

  9. Data Recovery: If you have backups, verify their integrity and use them to restore your systems. Having reliable backups is key to recovering quickly from a ransomware attack.

  10. Review and Update Security Measures: After the incident, review your security measures and update them as necessary to prevent future attacks. This includes overhauling security settings, reviewing external connection points, and ensuring all systems have up-to-date antivirus software so the attackers are not in the system.

  11. Get in Touch with Your Legal Team: Implement the incident response plan developed in advance with the help of qualified consultants. Utilize data restoration procedures that have been practiced and refined over time.

  12. Cryptocurrency Tracking and Investigation: Incorporate cryptocurrency tracking and reporting into your incident response plan. Tools like Chainalysis Reactor can help trace stolen assets and identify suspicious addresses.

Recommended Preventive Security Measures

The Kokubu Seikyo Hospital ransomware attack emphasizes the need for robust security practices within healthcare institutions. Key security measures that can help prevent similar incidents include:

Regular Security Audits: Implementing cybersecurity programs like NIST CSF 2.0 and conducting frequent security audits to identify and address vulnerabilities before they are exploited.

Employee Training: Ensuring that all employees are trained in the latest cybersecurity practices to mitigate the risk of insider threats and social engineering attacks.

Incident Response Plans: Developing and regularly updating incident response plans to ensure the organization can quickly and effectively respond to security breaches.

Practice Tabletop Exercises: Regularly conducting tabletop exercises helps prepare your team for actual incidents by simulating potential attack scenarios and improving response strategies.

Notes from the CISO

Why Image Management Server?

The image management server at Kokubu Seikyo Hospital is crucial for storing and managing medical images such as X-rays, MRIs, and CT scans. These servers contain sensitive patient health information (PHI), making them high-value targets for cybercriminals. Unauthorized access to this data can lead to severe privacy violations and potential misuse, impacting both patient care and hospital operations.

Hackers can exploit access to this server in several ways:

  1. Medical images and associated data can be used to steal patient identities, leading to financial fraud and privacy breaches.
  2. By encrypting medical images, hackers can halt critical healthcare services, forcing hospitals to pay ransoms to regain access.
  3. Stolen medical records and images can be sold on the dark web, fetching high prices due to their sensitive nature.

Impact on Hospital and Patients:

  • Any downtime affects emergency and routine outpatient services, delaying diagnoses and treatments.
  • Breaches can result in severe legal penalties and financial losses due to non-compliance with data protection regulations.

The Kokubu Seikyo Hospital ransomware attack serves as a critical reminder of the importance of robust cybersecurity measures and timely reporting. The initial response of disconnecting from the internet and reporting the incident was crucial in containing the breach. Immediate reporting of such incidents not only aids in faster investigation but also helps in preventing further attacks. At Gftd Japan, we emphasize the importance of prompt reporting and robust incident response plans.

The Kokubu Seikyo Hospital case also highlights the necessity for healthcare institutions to adopt advanced cybersecurity measures and continuously update their security protocols. By leveraging the latest tools and adhering to global security standards, healthcare providers can better protect their systems and patient data.

Healthcare organizations should commit to learning from this incident and strengthen their security infrastructure to protect patients’ information and maintain their trust in medical services. We encourage all organizations in the healthcare industry to review their own security measures in light of this incident to prevent similar attacks in the future.

If your organization needs assistance in strengthening its cybersecurity framework, contact Gftd Japan. Our expertise in cybersecurity solutions can help safeguard your digital assets and enhance your overall security posture. Book a call with us today to learn more about how we can help.



The ransomware attack on Kokubu Seikyo Hospital underscores the critical need for robust cybersecurity measures in healthcare institutions. By implementing advanced security practices and continuously monitoring and improving their systems, healthcare providers can better protect their assets and maintain the trust of their patients. For organizations seeking to enhance their cybersecurity measures, consulting with experts like Gftd Japan can provide the necessary tools and strategies to safeguard digital assets effectively.