INSPECTING ARCHIVED INTELLIGENCE (OUTDATED VERSION).

Everest Ransomware Organization Claims to Have Stolen Data from Firm

| 2026-10-17 13:54 CRITICAL LOW RANSOMWARE & EXTORTION DATA BREACH
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Executive Summary
AI-generated
On October 17, 2026, the international ransomware organization Everest claimed to have stolen over 263GB of data from South Korean network security firm Taekwang Network Information. The attackers posted content on their website focusing on Taekwang's information, targeting a total of 75 organizations and companies, including those in various sectors such as medical institutions, financial companies, public institutions, educational institutions, and game companies. Everest allegedly registered Taekwang as a victim company on its Dark Web release site and secured over 54,000 files, which include internal business materials, customer-specific network construction and operation materials, firewall settings, maintenance records, source code, and personal information. The authenticity of the released materials remains unclear, but if true, this incident highlights potential security risks in supply chains due to exposed security equipment settings and network configurations.
Technical Mitigations AI-generated
• Block or hunt for the Dark Web release site used by Everest ransomware organization to post stolen data. • Use a network traffic analysis tool to detect and monitor potential security risks related to supply chain exposure, such as unusual firewall settings or authentication system anomalies. • Implement a threat intelligence platform to identify and categorize external organizations, companies, facilities, and brands mentioned in the attacker's description.
Intelligence Metadata
Actors / Malware / CVEs / Campaigns
Target & Sectors
JP
healthhealth financefinance technologytechnology manufacturingmanufacturing educationeducation
Incident Timeline
‎2026/10/17
Everest ransomware organization posted content on its website claiming to have stolen 263.71GB of data from Taekwang Network Information, a South Korean network security firm.
organisation Everest Ransomware Organization
Exclusive: Everest Ransomware Organization Claims to Have Stolen 263GB of Data from South Korean Network Security Firm, Threatens to Expose 75 Organizations and Companies.
organisation South Korean Network Security Firm
Exclusive: Everest Ransomware Organization Claims to Have Stolen 263GB of Data from South Korean Network Security Firm, Threatens to Expose 75 Organizations and Companies.
data_breach 263 GB
Exclusive: Everest Ransomware Organization Claims to Have Stolen 263GB of Data from South Korean Network Security Firm, Threatens to Expose 75 Organizations and Companies.
victims 75 Organizations
Exclusive: Everest Ransomware Organization Claims to Have Stolen 263GB of Data from South Korean Network Security Firm, Threatens to Expose 75 Organizations and Companies.
A total of 75 external organizations, companies, facilities, and brands were identified, excluding Taewon Network Information.
Therefore, the 75 listed names should not be interpreted as 75 affected companies or 75 customer companies, but rather as actual customer relationships and reference materials that need to be verified by comparing the original file and contract and business history.
organisation Taekwang Network Information
Everest ransomware organization has posted content on its website, focusing on Taekwang Network Information.
organisation Taewon Network Information
A total of 75 external organizations, companies, facilities, and brands were identified, excluding Taewon Network Information.
organisation Dark
The attackers claim to have stolen data exceeding 263.71GB, and posted related content on a Dark Web release site.
data_breach 263.71 GB
The attackers claim to have stolen data exceeding 263.71GB, and posted related content on a Dark Web release site.
However, the data volume of 263.71GB and the number of secured files, as claimed by the attackers, have not been independently verified.
organisation Daily Security
According to cybersecurity intelligence materials secured by Daily Security on the 17th, Everest claimed to have registered Taekwang Network Information as a victim company on its own Dark Web release site and secured a total of 54,581 files.
data_breach 54,581 files
According to cybersecurity intelligence materials secured by Daily Security on the 17th, Everest claimed to have registered Taekwang Network Information as a victim company on its own Dark Web release site and secured a total of 54,581 files.
organisation OO University OO Central Hospital's
In particular, the medical sector mentioned OO University OO Central Hospital's four affiliated hospitals, each by name.
organisation Korean OO Research Institute
The finance sector included Japanese banks and domestic and foreign financial institutions, while the public sector included Korean OO Research Institute, Seoul OO Corporation, public service, and research-related institutions.
organisation Seoul OO Corporation
The finance sector included Japanese banks and domestic and foreign financial institutions, while the public sector included Korean OO Research Institute, Seoul OO Corporation, public service, and research-related institutions.
organisation IP
This includes customer-specific IP address systems, network segment-specific connection structures, firewall policies, remote access methods, management interfaces, and disaster response records.
organisation Shinhan Bank
Note: Shinhan Bank, KB Kookmin Bank, Hana Bank
organisation KB Kookmin Bank
Note: Shinhan Bank, KB Kookmin Bank, Hana Bank
organisation Hana Bank
Note: Shinhan Bank, KB Kookmin Bank, Hana Bank
organisation Taegwang Network Information
The current confirmed information is a claim of the impact on supply chain security, but it is not evidence that Everest has actually breached the customer's system through Taegwang Network Information.
Tactical Metrics
Metrics
data_breach
263
Gb
Exclusive: Everest Ransomware Organization Claims to Have Stolen 263GB of Data from South Korean Network Security Firm, Threatens to Expose 75 Organizations and Companies.
Metrics
victims
75
Organizations
Exclusive: Everest Ransomware Organization Claims to Have Stolen 263GB of Data from South Korean Network Security Firm, Threatens to Expose 75 Organizations and Companies.
A total of 75 external organizations, companies, facilities, and brands were identified, excluding Taewon Network Information.
Therefore, the 75 listed names should not be interpreted as 75 affected companies or 75 customer companies, but rather as actual customer relationships and reference materials that need to be verified by comparing the original file and contract and business history.
Metrics
data_breach
264
Gb
The attackers claim to have stolen data exceeding 263.71GB, and posted related content on a Dark Web release site.
However, the data volume of 263.71GB and the number of secured files, as claimed by the attackers, have not been independently verified.
Metrics
data_breach
54,581
Files
According to cybersecurity intelligence materials secured by Daily Security on the 17th, Everest claimed to have registered Taekwang Network Information as a victim company on its own Dark Web release site and secured a total of 54,581 files.
Intelligence Sources
Dailysecu 2026-10-17