^.^;

SIEM Deployment

Deploy Splunk, ELK Stack, QRadar. Log aggregation. Correlation rules. Real-time threat detection.

AdvancedPhase 3: Password SecurityInteractive Dashboard

What is SIEM?

SIEM (Security Information and Event Management) aggregates logs from across your infrastructure (firewalls, servers, endpoints, applications), correlates events, detects threats, and provides centralized visibility. Think of it as the "brain" of your security operations center.

Core SIEM Functions:

  • Log Aggregation: Collect logs from firewalls, IDS/IPS, Active Directory, web servers, etc.
  • Correlation: Connect related events (e.g., failed login → privilege escalation → data exfil)
  • Alerting: Real-time notifications for suspicious activity based on rules
  • Compliance: Meet regulatory requirements (PCI-DSS, HIPAA, SOX, GDPR)

Popular SIEM Platforms

📊 Splunk

Industry leader, powerful search (SPL)

  • • Best-in-class search & visualization
  • • Massive app marketplace (1000+ integrations)
  • • Splunk ES (Enterprise Security) for SOC
  • • Expensive licensing (per GB/day)

🔍 Elastic Stack (ELK)

Open-source, Elasticsearch backend

  • • Elasticsearch (search) + Logstash (ingestion) + Kibana (viz)
  • • Free & open-source core
  • • Elastic SIEM for security use cases
  • • Steep learning curve, resource-intensive

🛡️ IBM QRadar

Enterprise SIEM with advanced analytics

  • • Strong correlation engine
  • • Flow-based network monitoring
  • • UBA (User Behavior Analytics)
  • • Complex deployment, expensive

☁️ Microsoft Sentinel

Cloud-native SIEM (Azure)

  • • Integrates with Microsoft 365, Azure AD
  • • KQL (Kusto Query Language)
  • • Serverless, scales automatically
  • • Best for Microsoft-heavy environments

Critical Log Sources to Ingest

🔥 Firewalls & Network:

Firewall allow/deny logs, IDS/IPS alerts (Suricata, Snort), VPN connections, proxy logs (Squid)

🖥️ Endpoints:

Windows Event Logs (Security, System, Application), Sysmon, EDR alerts (CrowdStrike, Carbon Black)

🔐 Active Directory:

Authentication events (4624, 4625), privilege escalation (4672), account creation/deletion

🌐 Web Servers:

Apache/Nginx access logs, error logs, ModSecurity WAF logs, application logs (PHP, Node.js)

☁️ Cloud Platforms:

AWS CloudTrail, Azure Activity Logs, GCP Cloud Logging, O365 audit logs

📧 Email Security:

Email gateway logs (Proofpoint, Mimecast), phishing attempts, spam filters

Detection Rules & Use Cases

🔓 Brute Force Detection

index=windows EventCode=4625
| stats count by src_ip
| where count > 10

Trigger: More than 10 failed login attempts from single IP within 5 minutes

⚠️ Privilege Escalation

index=windows EventCode=4672
| where user NOT IN (admin_whitelist)

Trigger: Non-admin user assigned admin privileges (possible lateral movement)

📤 Data Exfiltration

index=firewall action=allowed bytes_out > 100MB
| where dest_ip NOT IN (trusted_clouds)

Trigger: Large outbound transfer to untrusted IP (potential data theft)

🦠 Malware Callback (C2)

index=dns query IN (known_c2_domains)
| join src_ip with firewall_logs

Trigger: DNS query to known command-and-control domain (threat intel match)

SIEM Deployment Architecture

1. Forwarders/Agents

Lightweight agents on endpoints/servers collect logs

  • • Splunk Universal Forwarder
  • • Elastic Beats (Filebeat, Winlogbeat)
  • • Syslog forwarders (rsyslog, syslog-ng)

2. Indexers/Storage

Central database stores and indexes logs

  • • Elasticsearch cluster (ELK)
  • • Splunk indexers (hot/warm/cold tiers)
  • • Retention: 90 days hot, 1 year warm, 7 years cold

3. Search Heads/Visualization

Frontend for analysts to query and investigate

  • • Kibana (ELK), Splunk Web, QRadar Console
  • • Dashboards, saved searches, alerting
  • • Role-based access control (RBAC)

Best Practices

Start Small: Ingest critical sources first (AD, firewall). Avoid "log explosion"
Tune Alerts: Reduce false positives. Alert fatigue kills SOC teams
Use Threat Intel: Feed IOCs (IPs, domains, hashes) into SIEM for automatic detection
Correlate Events: Single event = noise. Chain of events = incident (e.g., scan → exploit → exfil)
Document Playbooks: SOC analysts need runbooks for each alert type
Monitor SIEM Health: Forwarder uptime, ingestion rate, storage capacity

Real-World Impact: Target Breach (2013)

Target had FireEye SIEM that detected the malware and alerted SOC team. Alerts were ignored.

What Went Wrong:

  • • ❌ SIEM generated alerts, but SOC ignored them (alert fatigue)
  • • ❌ No escalation process for critical alerts
  • • ❌ Attackers exfiltrated 40 million credit card numbers over weeks

Lessons Learned:

  • • ✅ SIEM is only as good as the humans monitoring it
  • • ✅ Tune alerts to reduce noise (balance sensitivity vs. false positives)
  • • ✅ Automate response with SOAR for critical alerts

SIEM Deployment Dashboard

Connect log sources, enable detection rules, and monitor security alerts in real-time.

0
Log Sources
0
Active Rules
0
Events Processed
0
Alerts Generated

Log Sources

Windows AD
Type:Authentication
Events/sec:0
Firewall (pfSense)
Type:Network
Events/sec:0
Web Server (Nginx)
Type:Application
Events/sec:0
EDR (CrowdStrike)
Type:Endpoint
Events/sec:0

Detection Rules

Brute Force Detection
Severity:high
Triggers:0
Privilege Escalation
Severity:critical
Triggers:0
Data Exfiltration
Severity:critical
Triggers:0
Malware C2 Callback
Severity:high
Triggers:0

Security Alerts

No alerts. Connect log sources, enable rules, and start monitoring.
Terms of ServiceLicense AgreementPrivacy Policy
Copyright © 2025 JMFG. All rights reserved.