Devereux Breach Incident Score: Analysis & Impact (DEV1764634230)

In this Rankiteo incident briefing, we review the Devereux breach identified under incident ID DEV1764634230.

The analysis begins with a detailed overview of Devereux's information like the linkedin page: https://www.linkedin.com/company/devereux, the number of followers: 24417, the industry type: Mental Health Care and the number of employees: 3869 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 651 and after the incident was 478 with a difference of -173 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 Devereux and their customers.

On 01 December 2025, Devereux Advanced Behavioral Health disclosed Data Breach and Ransomware Attack issues under the banner "Devereux Advanced Behavioral Health Data Breach and Ransomware Attack".

The ransomware group known as The Gentlemen announced a breach targeting Devereux Advanced Behavioral Health on or about November 28, 2025.

The disruption is felt across the environment, and exposing True.

In response, and stakeholders are being briefed through Public disclosure via Globe Newswire; legal investigation announced by Edelson Lechtzin LLP.

The case underscores how Ongoing (class action investigation by Edelson Lechtzin LLP; breach details under assessment), and recommending next steps like Monitor account statements and credit reports for suspicious activity (advised to affected individuals) and Engage legal counsel for potential class action participation (via Edelson Lechtzin LLP), with advisories going out to stakeholders covering General advisory to monitor personal data for identity theft/fraud; link provided for legal consultation (HERE).

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 Exploit Public-Facing Application (T1190) with moderate confidence (60%), supported by evidence indicating ransomware group known as The Gentlemen announced a breach (no specific vector, but common for ransomware) and Valid Accounts (T1078) with moderate confidence (50%), supported by evidence indicating no explicit evidence, but common for ransomware groups like The Gentlemen to abuse valid accounts. Under the Exfiltration tactic, the analysis identified Exfiltration Over Alternative Protocol: Exfiltration Over Unencrypted/Obfuscated Non-C2 Protocol (T1048.003) with high confidence (90%), with evidence including data exfiltration such as true, and threatened to release confidential personal information. Under the Impact tactic, the analysis identified Data Encrypted for Impact (T1486) with moderate to high confidence (70%), with evidence including type such as Ransomware Attack, and the Gentlemen (ransomware group) and Data Destruction (T1485) with moderate confidence (50%), supported by evidence indicating threatened to release confidential personal information (implied data manipulation/destruction risk). Under the Lateral Movement tactic, the analysis identified Remote Services: Remote Desktop Protocol (T1021.001) with lower confidence (40%), supported by evidence indicating no direct evidence, but RDP is a common lateral movement vector in ransomware attacks. Under the Defense Evasion tactic, the analysis identified Impair Defenses: Disable/Modify Tools (T1562.001) with moderate confidence (60%), supported by evidence indicating ransomware attacks often disable security tools; no explicit evidence but highly likely. Under the Credential Access tactic, the analysis identified OS Credential Dumping (T1003) with moderate confidence (50%), supported by evidence indicating common in ransomware attacks for privilege escalation; no direct evidence but inferred from group TTPs. These correlations help security teams understand the attack chain and develop appropriate defensive measures based on the observed tactics and techniques.