Week 34, 2025 security incident report
Hacking and data breach incidents newly reported 2025.08.18 ~ 08.24
Between 18 and 24 August 2025, five new incidents were recorded in South Korea, with the theft of about 39 billion won through hacking targeting South Korean celebrities and wealthy individuals standing out as the largest financial loss. In the financial sector, a ransomware attack on a Welcome Financial Group affiliate along with claims of 1 TB of stolen data and a customer data leak at a Welcome-affiliated lending company were reported, and hacking damage related to card use at petrol stations also followed. A ruling also found that a fine over the leak of 1.13 million personal records at Daesung Mimac was lawful, and in the tally of all types, personal data leaks numbered 38, more than hacking/intrusion (10) and ransomware (5). Overseas, 48 new incidents were recorded, with leaks or exposures of personal or staff data occurring at Workday, Farmers Insurance, Auchan and Intel, whilst Inotiv suffered both a personal data leak and a shutdown of business systems due to ransomware.
By type
- Data breach37
- Hacking & intrusion10
- Ransomware5
Key incidents in South Korea
Hackers steal 39 billion won targeting Jungkook and other Korean celebrities and wealthy individuals
Impact: About 39 billion won
A hacking ring stole 39 billion won by targeting South Korean celebrities and wealthy individuals, including BTS member Jungkook and executives of major conglomerates. The crimes involved unauthorised activation of budget mobile (MVNO) phone lines, and military service members and prison inmates were also targeted. The ring's leader was arrested in Thailand and forcibly repatriated to South Korea.
Related reports: 6 · last report →Welcome Financial Group affiliate hit by ransomware attack
Impact: Claimed theft of 1TB of data
An affiliate of Welcome Financial Group was hit by a ransomware attack. The group said it was working to recover from the damage, while the hacking group claimed to have stolen 1TB of data.
Related reports: 5 · last report →Court upholds fine against Daesung Mimac over leak of 1.13 million personal records
1.1mImpact: 1.13 million personal records
1.13 million personal records were leaked from Daesung Mimac. An administrative court ruled that the related fine of around 600 million won was lawful.
Read on 비즈한국 ↗Welcome-affiliated lender hacked, customer data leaked
Impact: Customer information leaked
A consumer lender affiliated with the Welcome group was hacked and customer information was leaked. The scale of the leak, the date of the incident and the follow-up response have not been confirmed.
Read on MBC 뉴스 ↗Spate of hacking cases linked to card use at petrol stations
There has been a series of cases in which people suffered hacking-related losses after using their cards at petrol stations. The specific extent of the damage, when it occurred and the response have not been confirmed.
Read on 미주한국일보 ↗
Key incidents in other countries
Workday CRM system breach leaks personal information
Impact: Personal information and contact details
Workday's customer relationship management system was hit by a social engineering attack, leaking personal information. Workday disclosed the breach, and it was suggested that the exposed information may have included contact details.
Related reports: 14 · last report →Inotiv ransomware attack disrupts operations and leaks personal data
9.5kImpact: Personal data of 9,542 people leaked and business systems disrupted
US drug research company Inotiv was hit by a ransomware attack in August 2025 that took down systems including databases and internal applications and disrupted operations. The number of people whose personal information was stolen was confirmed at 9,542, and the company began notifying victims.
Related reports: 12 · last report →Farmers Insurance data breach affects 1.1 million customers
1.1mImpact: Personal information of about 1.1 million people
Personal information of about 1.1 million people was leaked at Farmers Insurance. The leak was linked to the Salesforce attacks and a cyber-attack on a third-party vendor. Farmers Insurance reported the breach to regulators.
Related reports: 10 · last report →French retailer Auchan leaks data of hundreds of thousands of customers
Impact: Data of hundreds of thousands of customers leaked
French retailer Auchan was hit by a cyber-attack that leaked customer information. Hundreds of thousands of customers were affected.
Related reports: 4 · last report →Flaw in Intel's internal business card site exposes data of 270,000 employees
270kImpact: Data of 270,000 employees
A researcher downloaded data on all 270,000 employees from Intel's internal business card website. The employee information was exposed through a website vulnerability, and the discovery was not eligible for a bug bounty reward.
Related reports: 3 · last report →