LinkedIn Breach Incident Score: Analysis & Impact (LINAWS1766995316)

In this Rankiteo incident briefing, we review the LinkedIn breach identified under incident ID LINAWS1766995316.

The analysis begins with a detailed overview of LinkedIn's information like the linkedin page: https://www.linkedin.com/company/linkedin, the number of followers: 33387235, the industry type: Software Development and the number of employees: 23908 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 832 and after the incident was 825 with a difference of -7 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 LinkedIn and their customers.

A newly reported cybersecurity incident, "FIN6 Skeleton Spider Campaign Targeting HR Professionals via Fake Job Applications", has drawn attention.

The financially motivated cybercrime group FIN6, also known as Skeleton Spider, is targeting human resources professionals with an elaborate social engineering scheme that uses fake job applications to deliver malware.

The disruption is felt across the environment, affecting HR systems, corporate networks, and exposing Credentials, sensitive employee data, system access.

In response, moved swiftly to contain the threat with measures like AWS Trust & Safety abuse reporting process, disabling prohibited content, and began remediation that includes Layered defenses, enhanced monitoring for unusual traffic patterns/file types, additional verification procedures for resume submissions.

The case underscores how teams are taking away lessons such as Traditional perimeter security is insufficient against social engineering tactics. Organizations must adopt holistic security strategies that account for human factors alongside technological defenses. HR personnel are increasingly targeted due to their regular interaction with external contacts, and recommending next steps like Implement comprehensive training programs for HR personnel on phishing and social engineering risks, Adopt additional verification procedures for resume submissions and external communications and Enhance monitoring for unusual traffic patterns or file types (e.g., ZIP files from unexpected sources).

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 Phishing: Spearphishing Link (T1566.002) with high confidence (95%), with evidence including phishing emails with malicious links, and fake resume sites mimicking real applicant names and Trusted Relationship (T1199) with high confidence (90%), supported by evidence indicating attackers pose as job seekers on LinkedIn/Indeed to build rapport with HR. Under the Execution tactic, the analysis identified Command and Scripting Interpreter: JavaScript (T1059.007) with high confidence (90%), supported by evidence indicating more_eggs backdoor operates as modular JavaScript malware and User Execution: Malicious File (T1204.002) with moderate to high confidence (85%), supported by evidence indicating malicious ZIP files containing More_eggs backdoor delivered to targets. Under the Persistence tactic, the analysis identified Browser Extensions (T1176) with moderate to high confidence (70%), supported by evidence indicating more_eggs backdoor operates in memory (implied persistence via browser/JS context). Under the Defense Evasion tactic, the analysis identified Hide Artifacts: Email Hiding Rules (T1564.008) with moderate to high confidence (80%), supported by evidence indicating traffic filtering to evade detection (IP reputation, geolocation, OS checks), Masquerading: Match Legitimate Name or Location (T1036.005) with high confidence (90%), supported by evidence indicating fake resume sites mimic real applicant names (e.g., bobbyweisman.com), Impair Defenses: Disable or Modify Tools (T1562.001) with moderate to high confidence (75%), supported by evidence indicating cAPTCHA walls bypass automated security scanners, and Valid Accounts: Cloud Accounts (T1078.004) with moderate to high confidence (85%), supported by evidence indicating abuse of AWS EC2/S3 to host malicious infrastructure. Under the Credential Access tactic, the analysis identified Credentials from Password Stores (T1555) with moderate to high confidence (80%), supported by evidence indicating more_eggs backdoor enables credential theft. Under the Discovery tactic, the analysis identified Account Discovery: Cloud Account (T1087.004) with moderate to high confidence (70%), supported by evidence indicating more_eggs malware enables follow-on attacks (implied discovery phase). Under the Command and Control tactic, the analysis identified Application Layer Protocol: Web Protocols (T1071.001) with moderate to high confidence (85%), supported by evidence indicating more_eggs backdoor operates in memory (likely C2 via web protocols). Under the Exfiltration tactic, the analysis identified Exfiltration Over C2 Channel (T1041) with moderate to high confidence (80%), supported by evidence indicating more_eggs enables follow-on attacks (implied data exfiltration). These correlations help security teams understand the attack chain and develop appropriate defensive measures based on the observed tactics and techniques.