A timeline of South Korean telco giant SKT’s data breach

In April, South Korea’s Telco Giant SK Telecom (SKT), about 23 million customers, led to the abduction of personal information from about half of the country to about half of the country.

Seoul in Seoul, at the meeting of the Milli Majlis, SKT CEO Young-Sang Ryu, 250,000 users were transferred to a different telecom provider after the information violation. This number will reach 2.5 million, more than the current amount, if the company eliminates its abolition fees, will be more than the current amount.

Ryu may lose to $ 5 billion (up to $ 7 trillion) to decide whether to cancel for users who want to cancel the contract for users who want to cancel the contract.

“SK Telecom reviews this incident in the history of the company and allows us to do our best to minimize any damage to our customers,” SKT said in a e-mail in TechCrunch. “The number of affected customers and the enterprise responsible for the hackeria is under investigation,” he said.

At present, the joint investigation is underway to determine the specific cause of the incident.

Personal Information Defense Committee (PIPC) South Korean declared Thursday It is 25 different personal information, including mobile phone numbers and unique identifiers (ITSI Numbers), as well as USIM identification buttons and other USIM data, a home subscriber known as a home subscriber. Discounted information can put customers in more risk SIM Changing Attacks and government control.

After Official announcement of the event on April 22SKT offers Customers to protect the SIM card and change free SIM card to avoid more damage.

“We have found a possible information leak on SIM on April 19,” he said. “After the return of the return, we areolated the device affected by immediate all system comprehensively.”

“To further protect our customers, we are currently developing a system that protects users using the SIM protection service while ensuring that Korea uses roaming services outside 14,” he said.

So far, the SKT did not receive any information about the secondary damage and there were no cases of distribution or abuse of customer information on the dark website or other platforms or not properly used on other platforms.

Schedule of SKT’s data breach

April 18, 2025

SKT detected abnormal activity On April 18 at 11:20 Local time. The SKT found unusual notes and file signs that have been deleted in the equipment used to monitor and manage shipping information to customers, including data use and call duration, including data use and call duration.

19 April 2025

The company determined the violation of a detailed information, which usually includes household owners, including subscriber data, including identification, authorization, location and mobility details.

April 20, 2025

The SKT reported the event of cyber Korean CyberSecure Agency On April 20th.

April 22, 2025

Skt Verified on the website Users discovered the suspicious activity that shows a “potential” information violation that covers some information related to USIMS data.

April 28, 2025

The SKT 23 million has begun to replace the user’s mobile SIM cards, but the company has Disadvantages of accessing enough USIM cards To fulfill the promise to provide SIM card replacement.

April 30, 2025

South Korean police began to investigate On April 18, SKT’s suspect cyberattack.

1 May 2025

According to local press newsMany South Korean companies, including SKT, Ivani VPN equipment, and the violation of the latest data can be connected to supported hackers in China.

Per Local Media ReportSKT, Kisa’dan Kibers received a cybersecime warning that the company instructs the company’s Ivandi VPN, he said.

TeamT5, Kiberecurity company located in Taiwan, He warned the people around the world by a The group that supports the government To get access to many organizations in the world, Ivani’s Connecture VPN has been closed to China.

Some 20 industries, including cars, chemistry, financial institutions, law firms, media, research institutes and telecommunications, including Australia, South Korea, Taiwan and the United States, including 12 countries.

6 May 2025

A group of social and private investigators discovered an additional eight types of harmful programs In the SKT’s Hacking Case. If the team is currently located in the original four floods or separate server equipment to the same home subscriber server of the new malicious program.

7 May 2025

Chairman of the SK group working on the SKT Tae-Won Chey, For the first time apologized For the violation, the violation occurred three weeks later.

As of May 7, all the appropriate users, the SIM protection service, using roaming services, using roaming services, using the cloned SIM cards using Press Secretary TechCrunch, added that all customers have been established to prevent unauthorized access attempts.

8 May 2028

The SKT assesses how to manage the cancellation fee for users affected by the information violation. According to the CEO of the Company, about 250,000 users passed to another telecom provider after violations.

South Korean government, in the meantime, 25 types of personal information were leaked from the company’s database during a cyberherattack.