Geisinger Breach Incident Score: Analysis & Impact (GEI1767779516)

In this Rankiteo incident briefing, we review the Geisinger breach identified under incident ID GEI1767779516.

The analysis begins with a detailed overview of Geisinger's information like the linkedin page: https://www.linkedin.com/company/geisinger, the number of followers: 84447, the industry type: Hospitals and Health Care and the number of employees: 15511 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 609 and after the incident was 592 with a difference of -17 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 Geisinger and their customers.

On 18 June 2025, a cybersecurity incident called "Ryuk Ransomware Initial Access Broker Extradited to U.S." came to light.

A 33-year-old foreign man, a member of the Ryuk ransomware operation specializing in gaining initial access to corporate networks, was arrested in Kyiv in April 2025 and extradited to the United States on June 18.

Impact assessments are still underway, so the full scope is not yet clear.

Formal response steps have not been shared publicly yet.

The case underscores how Ongoing (suspect extradited to U.S.).

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 Valid Accounts (T1078) with high confidence (90%), supported by evidence indicating specialized in gaining initial access to corporate networks, Exploit Public-Facing Application (T1190) with moderate to high confidence (70%), supported by evidence indicating initial Access Broker targeting corporate networks, and External Remote Services (T1133) with moderate to high confidence (70%), supported by evidence indicating ryuk ransomware’s initial access expert. Under the Credential Access tactic, the analysis identified Valid Accounts (T1078) with moderate to high confidence (80%), supported by evidence indicating specialized in gaining initial access to corporate networks and Brute Force (T1110) with moderate confidence (60%), supported by evidence indicating initial Access Broker (common tactic for Ryuk). Under the Defense Evasion tactic, the analysis identified Valid Accounts (T1078) with moderate to high confidence (80%), supported by evidence indicating used to bypass security controls in corporate networks and Impair Defenses: Disable or Modify Tools (T1562.001) with moderate to high confidence (70%), supported by evidence indicating ryuk ransomware known for disabling security tools. Under the Impact tactic, the analysis identified Data Encrypted for Impact (T1486) with high confidence (90%), supported by evidence indicating ryuk ransomware strain identified. Under the Exfiltration tactic, the analysis identified Exfiltration Over C2 Channel (T1041) with moderate to high confidence (70%), supported by evidence indicating ryuk ransomware known for data exfiltration. These correlations help security teams understand the attack chain and develop appropriate defensive measures based on the observed tactics and techniques.