Infosec Journey

Most medium to large organizations deploy a range of security tools—endpoint protection, file integrity monitoring (FIM), SIEM, and more. These tools often generate their own reports and benchmarks. The true value emerges when their data is correlated in real time. This integrated approach can reveal malicious activity or insider threats that otherwise stay undetected for weeks or even months.

For example:

• In the SolarWinds supply chain attack, the compromise went undetected for months due to lack of cross-tool correlation.
• In a 2022 healthcare ransomware incident, FIM flagged mass file changes. The SOC realized it was ransomware only after EDR data was correlated. Initially, they thought it was a misconfigured backup.

Let’s deep dive into a ransomware scenario. Assume the organization uses a defense-in-depth strategy with EDR, FIM, and SIEM/SOAR. Familiarity with the MITRE ATT&CK framework is assumed—specifically:

• T1486 (Data Encrypted for Impact): Ransomware encrypts files to extort victims.
• T1059 (Command and Scripting Interpreter): Ransomware often leverages PowerShell or cmd to execute payloads.

FIM Baseline: Monitor critical directories (e.g., /home/users, /srv/data) for:

• Mass file modifications
• Extension changes (e.g., .docx → .locked)
• Unauthorized deletions

Alert Thresholds: Trigger high-severity alerts if >50 files are changed or renamed within 2 minutes. Tag events matching known ransomware indicators.

EDR Policies: Enable ransomware protection to detect encryption-like behavior and mass file writes. Set up automated responses to:

• Auto-isolate the affected endpoint
• Terminate malicious processes

SIEM/SOAR Correlation:
All FIM and EDR alerts are forwarded to the SIEM, enriched with MITRE ATT&CK technique tags. A correlation rule triggers an “Active Ransomware Incident” if:

• FIM reports mass file changes (T1486)
• AND EDR detects ransomware-like process behavior (T1486, T1059) on the same host within a short window

The SOAR platform then:

• Confirms endpoint isolation
• Notifies the security team
• Launches forensic collection (logs, memory, etc.)
• Initiates backup restoration for affected files

If FIM and EDR work in silos, confirming a ransomware attack is delayed, increasing potential damage. Weak SIEM correlation further slows response. It forces the SOC team to triage incidents with less urgency. This leads to missing critical threats.

Having security tools in place is only the first step. Unlocking their true value requires smart correlation and streamlined processes. These processes transform isolated data into actionable, organization-wide defense.