Incident Score: Analysis & Impact (MAS1780929338)
The details regarding individual company incidents & reports gives you full view from every side.
Rankiteo Score Impact Analysis
Key Highlights From The Incident Analysis
- Timeline of MasTec's Ransomware and lateral movement inside company's environment.
- Overview of affected data sets, including SSNs and PHI, and why they materially increase incident severity.
- How Rankiteo’s incident engine converts technical details into a normalized incident score.
- How this cyber incident impacts MasTec Rankiteo cyber scoring and cyber rating.
- Rankiteo’s MITRE ATT&CK correlation analysis for this incident, with associated confidence level.
Full Incident Analysis Transcript
In this Rankiteo incident briefing, we review the MasTec breach identified under incident ID MAS1780929338.
The analysis begins with a detailed overview of MasTec's information like the linkedin page: https://www.linkedin.com/company/mas-tec, the number of followers: 47013, the industry type: Construction and the number of employees: 4070 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 777 and after the incident was 684 with a difference of -93 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 MasTec and their customers.
On 05 June 2026, MasTec Inc. disclosed Data Breach issues under the banner "MasTec Data Breach Affecting Over 25,000 Individuals".
MasTec Inc., a Florida-based infrastructure engineering and construction firm, reported a data breach impacting 25,220 individuals across the U.S.
The disruption is felt across the environment, affecting Limited portion of company’s systems, and exposing Personal information including names, Social Security numbers, dates of birth, and financial details, with nearly 25220 records at risk.
In response, and stakeholders are being briefed through Written letters to affected individuals beginning May 11, 2026.
The case underscores how Completed, with advisories going out to stakeholders covering Free membership to Financial Shield (credit and identity-theft monitoring service) offered 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.
MITRE ATT&CK® Correlation Analysis
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 Exploit Public-Facing Application (T1190) with moderate confidence (50%), supported by evidence indicating unauthorized party had accessed a limited portion of the company’s systems and Valid Accounts (T1078) with moderate confidence (60%), supported by evidence indicating network intrusion detected; likely used compromised credentials. Under the Execution tactic, the analysis identified User Execution: Malicious File (T1204.002) with moderate to high confidence (70%), supported by evidence indicating cL0P ransomware group claimed responsibility for the attack. Under the Persistence tactic, the analysis identified Valid Accounts (T1078) with moderate confidence (60%), supported by evidence indicating unauthorized access persisted from August to October 2025. Under the Credential Access tactic, the analysis identified OS Credential Dumping (T1003) with moderate to high confidence (70%), supported by evidence indicating names, Social Security numbers, dates of birth compromised and Unsecured Credentials: Credentials In Files (T1552.001) with moderate confidence (60%), supported by evidence indicating financial details and PII exfiltrated; likely accessed via files. Under the Discovery tactic, the analysis identified Account Discovery (T1087) with moderate confidence (60%), supported by evidence indicating 25,220 individuals affected; likely targeted high-value accounts and File and Directory Discovery (T1083) with moderate to high confidence (70%), supported by evidence indicating data-review firm analyzed compromised files post-breach. Under the Collection tactic, the analysis identified Data from Local System (T1005) with moderate to high confidence (80%), supported by evidence indicating names, SSNs, dates of birth, financial details compromised and Data Staged: Local Data Staging (T1074.001) with moderate to high confidence (70%), supported by evidence indicating cL0P group exfiltrated sensitive data before disclosure. Under the Exfiltration tactic, the analysis identified Exfiltration Over C2 Channel (T1041) with high confidence (90%), supported by evidence indicating cL0P ransomware group claimed responsibility for data exfiltration and Exfiltration Over Web Service: Exfiltration to Cloud Storage (T1567.002) with moderate confidence (60%), supported by evidence indicating data posted on Tor network; likely used cloud/storage services. Under the Impact tactic, the analysis identified Data Encrypted for Impact (T1486) with lower confidence (40%), supported by evidence indicating ransomware attack; no confirmation of encryption in incident details and Defacement: Internal Defacement (T1491.001) with lower confidence (30%), supported by evidence indicating cL0P group posted on Tor network to assert data theft. These correlations help security teams understand the attack chain and develop appropriate defensive measures based on the observed tactics and techniques.
Sources & References
- MasTec Rankiteo Cyber Incident Details: https://www.rankiteo.com/company/mas-tec/incident/MAS1780929338
- MasTec CyberSecurity Rating page: https://www.rankiteo.com/company/mas-tec
- MasTec Rankiteo Cyber Incident Blog Article: https://blog.rankiteo.com/mas1780929338-mastec-inc-ransomware-august-2025/
- MasTec CyberSecurity Score History: https://www.rankiteo.com/company/mas-tec/history
- MasTec CyberSecurity Incident Source: https://www.claimdepot.com/data-breach/mastec-2026
- Rankiteo A.I CyberSecurity Rating methodology: https://www.rankiteo.com/Images/rankiteo_algo.pdf
- Rankiteo TPRM Scoring methodology: https://static.rankiteo.com/model/rankiteo_tprm_methodology.pdf