SEIU Local 1000 Breach Incident Score: Analysis & Impact (SEI1769024138)

In this Rankiteo incident briefing, we review the SEIU Local 1000 breach identified under incident ID SEI1769024138.

The analysis begins with a detailed overview of SEIU Local 1000's information like the linkedin page: https://www.linkedin.com/company/seiu-local-1000, the number of followers: 2058, the industry type: Government Relations Services and the number of employees: 237 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 753 and after the incident was 669 with a difference of -84 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 SEIU Local 1000 and their customers.

On 30 May 2025, Civil Service Employees Association, Inc., Local 1000, AFSCME, AFL-CIO (CSEA Local 1000) disclosed Data Breach issues under the banner "CSEA Local 1000 Data Breach Exposes Sensitive Information of Over 47,000 Individuals".

A cybersecurity incident involving the Civil Service Employees Association, Inc., Local 1000, AFSCME, AFL-CIO (CSEA Local 1000) exposed the personally identifiable information (PII) of 47,352 individuals nationwide.

The disruption is felt across the environment, and exposing Personally identifiable information (PII) including full names and Social Security numbers, with nearly 47,352 records at risk.

In response, teams activated the incident response plan, moved swiftly to contain the threat with measures like Affected systems taken offline, and stakeholders are being briefed through Written notifications to affected individuals.

The case underscores how Completed, with advisories going out to stakeholders covering Written notifications sent to affected individuals.

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 moderate to high confidence (70%), supported by evidence indicating unauthorized party accessed its systems between May 3 and May 31, 2025 and Exploit Public-Facing Application (T1190) with moderate confidence (50%), supported by evidence indicating suspicious activity on its systems, took affected systems offline. Under the Credential Access tactic, the analysis identified Modify Authentication Process (T1556) with moderate confidence (60%), supported by evidence indicating social Security numbers and full names compromised and OS Credential Dumping (T1003) with moderate confidence (50%), supported by evidence indicating unauthorized party accessed systems containing sensitive data. Under the Collection tactic, the analysis identified Data from Local System (T1005) with moderate to high confidence (80%), supported by evidence indicating files containing sensitive data...compromised and Data from Information Repositories (T1213) with moderate to high confidence (70%), supported by evidence indicating pII of 47,352 individuals exposed. Under the Exfiltration tactic, the analysis identified Exfiltration Over C2 Channel (T1041) with moderate to high confidence (70%), supported by evidence indicating 47,352 individuals PII exposed in breach and Transfer Data to Cloud Account (T1537) with moderate confidence (50%), supported by evidence indicating unauthorized party accessed systems for nearly a month. Under the Impact tactic, the analysis identified Data Destruction (T1485) with lower confidence (40%), supported by evidence indicating systems taken offline after detecting suspicious activity and Data Manipulation: Stored Data Manipulation (T1565.001) with lower confidence (30%), supported by evidence indicating potential claims under evaluation for affected individuals. These correlations help security teams understand the attack chain and develop appropriate defensive measures based on the observed tactics and techniques.