Log Sources: OS, Network, and Application Logs
Understand what Windows Event Logs, syslog, Apache/Nginx logs, and firewall logs contain.
Why Logs Matter
Logs are the primary evidence source for security investigations. Every login, network connection, and application action leaves a trace. Without logs, attacks are invisible and forensic reconstruction is impossible.
Windows Event Logs
Windows organizes logs into channels: Security, System, Application, and custom application channels. The Security log contains authentication, access control, and audit events — most important for security analysis.
# View Windows Event Logs
# Event Viewer (GUI): eventvwr.msc
# PowerShell
Get-EventLog -LogName Security -Newest 50
Get-WinEvent -LogName Security | Where-Object {$_.Id -eq 4625}
# Key Security Event IDs:
# 4624: Logon success
# 4625: Logon failure
# 4648: Explicit credentials
# 4672: Admin logonAll lessons in this course
- Log Sources: OS, Network, and Application Logs
- SIEM Architecture and Log Ingestion
- Writing Detection Rules and Correlation
- Alert Triage and SOC Workflow