Best Practices - Logging, Monitoring & Threat Detection
Why Logging & Monitoring Matters
Logging and monitoring provide the visibility needed to detect, investigate, and respond to security and operational issues. Without proper logs or alerting, incidents may go unnoticed, and root causes may remain unclear.
Common Risks
| Risk | Description | Key Controls (At a Glance) |
|---|---|---|
Insufficient Logging | Blind spots prevent incident detection and investigation. | Log all auth, privilege, config, and application errors. |
Local-Only Logs | Attackers routinely delete local logs to hide tracks; data is lost if hardware fails. | Forward logs to a central SIEM; restrict access; ensure immutability. |
Log Leakage | Poor configs dump passwords, API keys, or PII into logs, creating a security risk. | Sanitize inputs; exclude restricted data from log outputs. |
No Active Review | Critical breach indicators accumulate unnoticed without automation. | Set automated alert rules; use dashboards; define escalations. |
Note:
The “Key Controls (At a Glance)” column is intended as a quick reference. Detailed expectations and implementation guidance are described in the Best Practices sections below.
Best Practices
Log Security-Relevant Events
Systems & Endpoints: * Authentication (success/failure, especially root/admin).
- Privilege changes (sudo usage, group updates).
- System mutations (config edits, clock adjustments, log clearing).
- Application faults (critical errors, web server crashes).
Network Devices: * Traffic filtering (firewall drops, rule matches).
- Remote access (VPN logins, session times, source IPs).
- Infrastructure changes (routing edits, ACL updates).
Centralize and Protect Logs
- Centralize: Forward system events to an enterprise SIEM in near-real-time.
- Synchronize (NTP): Sync all system clocks to institutional NTP servers to ensure accurate cross-system incident timelines.
- Secure: Enforce least-privilege (read-only for admins, append-only for systems) and encrypt logs in transit (TLS) and at rest.
Define Alerting Rules
- Deploy Core Alerts: Target brute-force logins, new admin creations, disabled security tools, and anomalous off-hours access.
- Reduce Noise: Tune alert thresholds regularly with your security team to combat alert fatigue.
Tune alerts to minimize noise while retaining meaningful signals.
Manage the Log Lifecycle
- Retention: Align storage timelines with institutional policies and legal mandates.
- Rotation: Automate log rotation and archiving to prevent disk space exhaustion and service outages.
Incorporate Monitoring into Operations
- Daily Workflow: Make dashboard and alert reviews part of daily administrative routines.
- Feedback Loops: Review log adequacy after every incident to continuously improve detection logic