Cytek Biosciences Breach Incident Score: Analysis & Impact (CYT1766447891)

In this Rankiteo incident briefing, we review the Cytek Biosciences breach identified under incident ID CYT1766447891.

The analysis begins with a detailed overview of Cytek Biosciences's information like the linkedin page: https://www.linkedin.com/company/cytek-biosciences, the number of followers: 32301, the industry type: Biotechnology Research and the number of employees: 442 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 690 with a difference of -62 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 Cytek Biosciences and their customers.

On 22 December 2025, Cytek Biosciences, Inc. disclosed Data Breach issues under the banner "Cytek Biosciences Data Breach".

Cytek Biosciences, Inc.

The disruption is felt across the environment, and exposing Personally identifiable information (PII) and protected health information (PHI).

In response, and stakeholders are being briefed through Dedicated toll-free response line (833-918-1243), official notice with credit bureau instructions.

The case underscores how and recommending next steps like Enroll in complimentary identity protection and credit monitoring services, Place a security freeze or fraud alert on credit files and Regularly review account statements and credit reports for suspicious activity, with advisories going out to stakeholders covering Affected individuals encouraged to enroll in identity protection services and monitor accounts.

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 employee account usernames and passwords exposed and Exploit Public-Facing Application (T1190) with moderate confidence (50%), supported by evidence indicating data breach disclosed; attack vector not specified. Under the Credential Access tactic, the analysis identified Unsecured Credentials: Credentials In Files (T1552.001) with moderate to high confidence (70%), supported by evidence indicating employee account usernames and passwords exposed. Under the Collection tactic, the analysis identified Data from Local System (T1005) with moderate to high confidence (80%), supported by evidence indicating pII and PHI compromised, including SSNs and medical records. Under the Exfiltration tactic, the analysis identified Exfiltration Over C2 Channel (T1041) with moderate to high confidence (70%), supported by evidence indicating high-sensitivity data exposed; exfiltration implied. Under the Impact tactic, the analysis identified Data Encrypted for Impact (T1486) with lower confidence (30%), supported by evidence indicating no ransomware strain identified; data encryption not confirmed and Data Manipulation: Transmitted Data Manipulation (T1565.002) with lower confidence (40%), supported by evidence indicating data breach disclosed; manipulation not confirmed. These correlations help security teams understand the attack chain and develop appropriate defensive measures based on the observed tactics and techniques.