[Report] "It's Not Enough Even If They Deliver It Themselves..." SKT Subscribers Turned Away on First Day of USIM Replacement

SK Telecom Stores Near Gangnam Station and Gwanghwamun Overwhelmed on First Day
Many Customers Leave Without USIM Replacement

"The line is so long, I don't think I'll be able to get it replaced today."

In front of the SK Telecom store near Gangnam Station in Seoul visited on the 28th, a long line formed early in the morning. Photo by Byun Seonjin

On April 28, the day SK Telecom began offering free USIM card replacement services in response to a recent hacking incident, the SK Telecom store near Gangnam Station in Seoul was already packed with customers early in the morning. Although there was still an hour left before the replacements would begin, more than 100 customers were already lined up, waiting for their turn.

SK Telecom had announced that starting at 10 a.m. that day, it would provide free USIM card replacements at over 2,600 SK Telecom stores (T World locations) nationwide for customers who wished to participate. Eligible customers are those who subscribed to SK Telecom's mobile services before midnight on April 18, the date when protective measures such as system isolation were implemented following the incident.

By 10 a.m., the number of people waiting had swelled to between 200 and 300. However, only 100 USIM cards had been prepared at this store for the initial batch. As a result, a significant number of customers were unable to replace their USIM cards and had to leave. A store employee advised, "Please make an online reservation for USIM replacement and visit again tomorrow," adding, "If you are particularly concerned, you can sign up for the USIM Protection Service first." Han, a 50-year-old customer who had been waiting since 9:40 a.m., expressed frustration, saying, "Do I have to line up again early in the morning tomorrow?"

The USIM Protection Service was developed in cooperation with the Seoul Metropolitan Police Agency's Cyber Investigation Unit in 2023 to prevent damage from illegal USIM cloning. According to SK Telecom, even if a hacking group steals or clones USIM information, the service blocks access to telecommunications services under the customer's name from other devices.

Even customers who managed to "open run"?arrive early and secure a spot?were confused by the store's notice stating that USIM replacement would only be possible after confirming an online reservation. At around 10:15 a.m., one customer showed that the number of people waiting online was as high as 75,000, and it took more than 10 minutes to complete the reservation. Some elderly customers expressed dissatisfaction, asking, "Why do we have to make an online reservation after coming all the way to the store?"

On the 28th, a notice related to the recent hacking incident was posted in front of the SK Telecom store in Gwanghwamun, Seoul. Photo by Eunseo Lee

Customers appeared to have lost trust in SK Telecom due to this incident. Kim, a 40-year-old customer, said, "I came to replace my USIM because I was anxious, but after this, I'm thinking of switching to another carrier." Han, 26, also said, "If another carrier offers good benefits, I'm willing to switch." Bae, 37, commented, "At this point, we should consider a class action lawsuit. Does it make sense that we have to line up every morning when they should be delivering the USIM cards to us?"

In front of the SK Telecom store in Gwanghwamun, a queue over 100 meters long had formed early in the morning as well. To prevent confusion, the store began handing out numbered tickets before 10 a.m., but with only 200 USIM cards available in the initial batch, most customers were unable to get their replacements. Some lingered in front of the store, disappointed. Choi Kyungja, 65, who came with a coworker to replace her USIM, said, "I received a voice phishing call a few days ago, and now this has happened. I'm worried that these scam calls will become even more frequent."

There have also been confirmed cases of people exploiting SK Telecom's free USIM replacement measure. As anxiety among subscribers grew following the USIM hacking incident, Acting President and Prime Minister Han Ducksoo instructed the Ministry of Science and ICT and other relevant agencies to "thoroughly review the appropriateness of measures such as signing up for the USIM Protection Service and replacing USIM cards." The Ministry of Science and ICT warned users to be cautious, stating that phishing and smishing attacks exploiting keywords such as "free USIM replacement" and "USIM Protection Service" have occurred.

There has also been criticism that SK Telecom's response to the hacking incident has been passive. Ahn Jimin, 48, who managed to replace her USIM after much difficulty, said, "I have a lot of financial information on my phone and had transactions to make today, so I came out early in the morning. I thought SK Telecom would at least send a text message, but I only found out about the situation through the news and YouTube."

Many customers interviewed that day expressed concerns about the risk of USIM information leakage and said SK Telecom must come up with measures to prevent a recurrence. Lee, 72, said, "The biggest problem is that the hacking happened because of poor security," adding, "I'm most worried that money could be stolen through mobile financial information."Kim Jiyeong, 55, an office worker near Gwanghwamun, said, "A USIM card is as important as an ID card, so I signed up for the USIM Protection Service immediately after the incident. The telecommunications industry is a key infrastructure sector, so strong government sanctions are needed."

Meanwhile, SK Telecom stated, "With so many customers showing a high level of concern about personal information security, if too many people visit stores at once on the first day of the replacement service, significant inconvenience is expected," and urged customers to actively use the online reservation system.