Week 24, 2026 security incident report
Hacking and data breach incidents newly reported 2026.06.08 ~ 06.14
From 8 to 14 June, seven new incidents were recorded in South Korea, with the leak of student and instructor personal data following a hack of Day1 Company drawing the most attention with 11 articles. Personal data damage continued across various industries, including the leak of passwords and home addresses at Fastcampus, personal data leaks at TVING and CU, and the exposure of resident registration numbers on the Gwangmyeong City Hall website, and the possible leak of 1 million congregant records was raised at two megachurches. Account compromises also occurred, as Hwang Shin-hye's YouTube channel, run for seven years, was deleted after being hacked and later restored, and across all types in South Korea and abroad, personal data leaks were the most common at 27. Overseas, among 54 new incidents, the leak of information on more than 450,000 University of Nottingham students and the shutdown of two Mackay Sugar mills stood out, and chain damage spreading from Synnovis to Mid and South Essex NHS Foundation Trust was also confirmed.
By type
- Data breach26
- Hacking & intrusion18
- Ransomware11
- Malware2
- DDoS1
Key incidents in South Korea
Day1 Company hack leaks students' and instructors' personal data
In June 2026, personal data was leaked in a hack of Day1 Company, the operator of Fast Campus, and damage to information on instructors and employees of Samsung, LG and Kakao was also confirmed. The leaked items included passwords and phone numbers, and a further leak of card and account information later came to light. Day1 Company said early on that it was assessing the scale of the damage, and criticism was later raised over its response and lack of communication.
Related reports: 11 · last report →Hwang Shin-hye's YouTube channel deleted after hack, later restored
Impact: Deletion of a YouTube channel run for seven years
Hwang Shin-hye's YouTube channel, which she had run for seven years, was deleted after being hacked. Work to restore the channel was carried out in mid-June, and in July it was reported that she was relieved at its restoration.
Related reports: 6 · last report →Online course platform FastCampus leaks passwords and home addresses
Impact: Personal information including passwords and home addresses
A personal data leak at online course platform FastCampus came to light on 10 June 2026. The leaked information included passwords and home addresses.
Related reports: 2 · last report →Series of personal data leaks at TVING, CU and FastCampus
Personal data leaks occurred one after another at TVING, CU and FastCampus. Along with the repeated leaks, risks of follow-on harm via phone calls were raised. The date, scale and response measures for each incident have not been confirmed.
Related reports: 2 · last report →Hack of two megachurches may have leaked 1 million congregant records
1mImpact: Possible leak of 1 million congregant records
Two large churches were hacked. The possibility was raised that 1 million records of congregant information were leaked.
Read on 라디오코리아 ↗NongHyup's customer response after data leak sparks controversy
NongHyup's handling of the aftermath of a personal data leak became controversial. The controversy included a statement to the effect that no customers felt anxious.
Read on 시사저널 ↗Resident registration numbers exposed on Gwangmyeong City Hall website
Impact: Exposure of resident registration numbers
A personal data leak occurred in which resident registration numbers were exposed on the Gwangmyeong City Hall website. The number of people affected, when it happened and any follow-up measures have not been confirmed.
Read on 시사팩트 ↗
Supply-chain breaches
Synnovis ransomware attack disrupts London hospital care and leaks patient data
900kImpact: More than 900,000 patients affected; about 1,600 surgery and care appointments cancelled in one week
UK pathology provider Synnovis was hit by a ransomware attack in 2024 that disrupted transfusions, surgery and care at London hospitals. Patient names, dates of birth, NHS numbers and test results that could be linked to some individuals were stolen, and more than 900,000 patients were affected. Hospitals used paper records, and after finishing its analysis of the stolen data, Synnovis began notifying affected healthcare organisations in November 2025.
Related reports: 38 · last report →
Also affected: 1- Mid and South Essex NHS Foundation TrustSynnovis cyber-attack leaks thousands of Essex NHS patient recordsThousands of patient records
Key incidents in other countries
University of Nottingham cyber-attack leaks data of over 450,000 students
450kImpact: Information of more than 450,000 students
The University of Nottingham was hit by a cyber-attack that leaked the information of more than 450,000 students. The university said a significant amount of data had been stolen, and ShinyHunters claimed the attack. The Malaysia campus assessed the impact, and the university later released further details about the incident.
Related reports: 10 · last report →Novo Nordisk cyber-attack leaks clinical trial patient data
Impact: Patient information from some clinical trials leaked
Novo Nordisk said a cyber-attack had leaked patient information from some clinical trials. The attackers later claimed to have also stolen drug research materials, clinical trial data and AI models. Whether the additional theft claims have been verified and the specific scale of the damage have not been disclosed.
Related reports: 7 · last report →Mackay Sugar cyber-attack halts two sugar mills
Impact: Two sugar mills halted and sugar cane harvest disrupted
The IT environment of Australian sugar producer Mackay Sugar was compromised, halting two sugar mills and disrupting the sugar cane harvest. The company worked to restore operations. The ransomware group Gentlemen claimed the attack, and the company said it was verifying the group's involvement and the extent of data access.
Related reports: 6 · last report →Xsolis data breach affects at least 9 healthcare systems and 1.4 million patients
1.4mImpact: At least nine healthcare systems and 1.4 million patients
Healthcare artificial intelligence company Xsolis suffered a data breach. The incident affected at least nine healthcare systems and 1.4 million patients. Xsolis issued a notification about the data security incident, and lawyers began an investigation.
Related reports: 5 · last report →ShinyHunters attack on PeopleSoft servers leaks university data
Impact: Personal information and data of higher education institutions using PeopleSoft
ShinyHunters attacked Oracle PeopleSoft servers and stole data from higher education institutions using them. Google said schools using Oracle software had been attacked and personal information leaked. The attacks exploited the PeopleSoft zero-day vulnerability CVE-2026-35273.
Related reports: 5 · last report →