LG Uplus Business Breach Incident Score: Analysis & Impact (LGU1767124813)

In this Rankiteo incident briefing, we review the LG Uplus Business breach identified under incident ID LGU1767124813.

The analysis begins with a detailed overview of LG Uplus Business's information like the linkedin page: https://www.linkedin.com/company/lguplus, the number of followers: 174, the industry type: Telecommunications and the number of employees: 9 employees

After the initial compromise, the video explains how Rankiteo's incident engine converts technical details into a normalized incident score. The incident score before the incident was 752 and after the incident was 549 with a difference of -203 which is could be a good indicator of the severity and impact of the incident.

In the next step of the video, we will analyze in more details the incident and the impact it had on LG Uplus Business and their customers.

On 30 December 2025, KT Corp disclosed Data Breach, Unauthorised Transactions, Malware Infection issues under the banner "KT Femtocell Security Breach Leading to Unauthorised Mobile Payments".

South Korea has blamed weak femtocell security at KT Corp for a major mobile payment breach that triggered thousands of unauthorised transactions.

The disruption is felt across the environment, affecting Femtocells, 94 KT servers, and exposing User identifiers, payment information, with nearly 22,000+ records at risk, plus an estimated financial loss of 243 million won (unauthorised payments).

In response, and began remediation that includes Planned security upgrades, compensation arrangements, and stakeholders are being briefed through Public acknowledgment of findings, commitment to improvements.

The case underscores how Completed (findings accepted by KT), teams are taking away lessons such as Inadequate femtocell security management, prolonged certificate validity, and lack of regular authentication updates can lead to major breaches. Strong information security is critical for national AI leadership, and recommending next steps like Change authentication server addresses regularly, Block illegal network access and Improve femtocell security management, with advisories going out to stakeholders covering Government urges operators to prioritize security, warns of survival risks in AI-driven economy.

Finally, we try to match the incident with the MITRE ATT&CK framework to see if there is any correlation between the incident and the MITRE ATT&CK framework.

The MITRE ATT&CK framework is a knowledge base of techniques and sub-techniques that are used to describe the tactics and procedures of cyber adversaries. It is a powerful tool for understanding the threat landscape and for developing effective defense strategies.

Rankiteo's analysis has identified several MITRE ATT&CK tactics and techniques associated with this incident, each with varying levels of confidence based on available evidence. Under the Initial Access tactic, the analysis identified Trusted Relationship (T1199) with moderate to high confidence (80%), with evidence including identical authentication certificates across femtocells, and unauthorized devices repeatedly accessed the network and External Remote Services (T1133) with moderate to high confidence (70%), supported by evidence indicating femtocell security flaws enabled unauthorized access. Under the Credential Access tactic, the analysis identified Unsecured Credentials: Private Keys (T1552.004) with high confidence (90%), supported by evidence indicating identical, long-term authentication certificates valid for a decade. Under the Lateral Movement tactic, the analysis identified Exploitation of Remote Services (T1210) with moderate to high confidence (70%), supported by evidence indicating 94 KT servers infected with over 100 types of malware. Under the Impact tactic, the analysis identified Resource Hijacking (T1496) with moderate to high confidence (80%), supported by evidence indicating unauthorized transactions totaling 243 million won and Account Access Removal (T1531) with moderate confidence (60%), supported by evidence indicating block illegal network access recommended post-incident. Under the Defense Evasion tactic, the analysis identified Install Root Certificate (T1553.004) with moderate to high confidence (70%), supported by evidence indicating prolonged certificate validity (10 years) without re-verification and Valid Accounts (T1078) with moderate to high confidence (80%), supported by evidence indicating unauthorized devices accessed network using weak certificates. Under the Exfiltration tactic, the analysis identified Exfiltration Over Alternative Protocol (T1048) with moderate confidence (60%), supported by evidence indicating user identifiers and payment information exposed. These correlations help security teams understand the attack chain and develop appropriate defensive measures based on the observed tactics and techniques.