Performing Purple Team Exercise

When to Use

Use this skill when:

• SOC teams need to validate that detection rules actually fire for the threats they target
• Red team assessments produced findings that need translation into detection improvements
• New detection tools or SIEM migrations require validation of detection coverage
• Analyst training requires hands-on experience with real attack techniques and SIEM responses
• Quarterly or semi-annual detection validation cycles are scheduled

Do not use for unannounced red team engagements — purple team exercises require explicit coordination between offensive and defensive teams with real-time collaboration.

Prerequisites

• Red team capability: internal team or contracted purple team operator
• Attack simulation tools: Atomic Red Team, MITRE Caldera, or C2 framework (authorized)
• SIEM access for real-time alert monitoring during exercise
• ATT&CK-mapped detection rule inventory with expected alert names
• Isolated test environment or approved production scope with change management approval
• Communication channel (Slack/Teams) for real-time red-blue coordination

Workflow

Step 1: Define Exercise Scope and Objectives

Document exercise parameters:

purple_team_exercise:
  exercise_id: PT-2024-Q1
  date: 2024-03-20
  duration: 8 hours (09:00-17:00 UTC)
  scope:
    environment: Production (Finance VLAN, 10.0.5.0/24)
    systems_in_scope:
      - WORKSTATION-TEST01 (10.0.5.100) — Test endpoint
      - DC-TEST (10.0.5.200) — Test domain controller
      - FILESERVER-TEST (10.0.5.201) — Test file server
    systems_excluded:
      - All production domain controllers
      - Customer-facing systems
  objectives:
    - Validate 15 detection rules mapped to FIN7 TTPs
    - Test SOC analyst response to real attack indicators
    - Identify detection gaps for credential access and lateral movement
    - Measure detection latency for each technique
  threat_scenario: FIN7 campaign targeting financial data via spearphishing
  authorization: Approved by CISO, Change Request CR-2024-0567
  communication: #purple-team-2024q1 Slack channel

Step 2: Build ATT&CK-Mapped Test Plan

Create technique-by-technique test matrix:

Step 3: Execute Red Team Techniques

Run each technique with Atomic Red Team (or manual execution):

# Install Atomic Red Team
IEX (IWR 'https://raw.githubusercontent.com/redcanaryco/invoke-atomicredteam/master/install-atomicredteam.ps1' -UseBasicParsing)
Install-AtomicRedTeam -getAtomics

# Test 1: T1059.001 — PowerShell Execution
Write-Host "[$(Get-Date -Format 'HH:mm:ss')] Executing T1059.001 - PowerShell"
Invoke-AtomicTest T1059.001 -TestNumbers 1
# Notify blue team: "T1059.001 executed at $(Get-Date)"

# Test 2: T1053.005 — Scheduled Task Creation

…