Agent skill

conducting-post-incident-lessons-learned

Facilitate structured post-incident reviews to identify root causes, document what worked and failed, and produce actionable recommendations to improve future incident response.

Stars 4,300
Forks 470

Install this agent skill to your Project

npx add-skill https://github.com/mukul975/Anthropic-Cybersecurity-Skills/tree/main/skills/conducting-post-incident-lessons-learned

SKILL.md

Conducting Post-Incident Lessons Learned

When to Use

  • After any security incident has been fully resolved and recovery completed
  • Following tabletop exercises or IR simulations
  • After significant near-miss events
  • Quarterly review of accumulated incident trends
  • When IR playbooks need updating based on real-world experience

Prerequisites

  • Incident fully resolved (containment, eradication, recovery complete)
  • Incident timeline and documentation gathered
  • All incident responders available for review session
  • Meeting space for collaborative discussion
  • Incident ticketing system data for metrics analysis

Workflow

Step 1: Gather Incident Data

bash
# Export incident timeline from ticketing system
curl -s "https://thehive.local/api/v1/case/$CASE_ID/timeline" \
  -H "Authorization: Bearer $THEHIVE_API_KEY" | jq '.' > incident_timeline.json

# Extract detection and response metrics from SIEM
index=notable incident_id="IR-2024-042"
| stats min(_time) as first_alert, max(_time) as last_alert,
  count as total_alerts, dc(src) as unique_sources

# Compile all responder actions and timestamps
grep -E "timestamp|action|analyst" /var/log/ir/IR-2024-042/*.json | \
  python3 -m json.tool > compiled_actions.json

Step 2: Conduct Blameless Post-Mortem Meeting

Structured Agenda (90 minutes):
1. Incident summary (5 min) - Factual overview
2. Timeline walkthrough (20 min) - Chronological events
3. What worked well (15 min) - Positive outcomes
4. What needs improvement (15 min) - Gaps and failures
5. Root cause analysis (15 min) - 5 Whys or fishbone
6. Action items (10 min) - Specific improvements with owners
7. Playbook updates (10 min) - Changes to IR procedures

Blameless Principles:
- Focus on systems and processes, not individuals
- Assume best intentions with available information
- Seek to understand, not to blame

Step 3: Perform Root Cause Analysis

bash
# 5 Whys analysis example:
# Why 1: Why did ransomware encrypt production servers?
#   Answer: Attacker had domain admin credentials
# Why 2: Why did attacker have domain admin credentials?
#   Answer: Kerberoasted a service account and cracked it
# Why 3: Why was the service account password crackable?
#   Answer: Used a 12-character dictionary-based password
# Why 4: Why was the service account password weak?
#   Answer: No enforcement of service account password policy
# Why 5: Why was there no service account password policy?
#   Answer: PAM was not implemented for service accounts
# ROOT CAUSE: Lack of privileged access management

Step 4: Calculate Response Metrics

python
from datetime import datetime
events = {
    'compromise': '2024-01-10 14:00:00',
    'detection': '2024-01-15 08:30:00',
    'triage': '2024-01-15 08:45:00',
    'containment': '2024-01-15 09:30:00',
    'eradication': '2024-01-16 14:00:00',
    'recovery': '2024-01-18 16:00:00',
    'closure': '2024-01-25 10:00:00',
}
fmt = '%Y-%m-%d %H:%M:%S'
times = {k: datetime.strptime(v, fmt) for k, v in events.items()}
print(f"Dwell Time: {times['detection'] - times['compromise']}")
print(f"MTTD: {times['triage'] - times['detection']}")
print(f"MTTC: {times['containment'] - times['detection']}")
print(f"MTTR: {times['recovery'] - times['eradication']}")
print(f"Total Duration: {times['closure'] - times['detection']}")

Step 5: Document Findings and Create Action Items

bash
# Create tracked action items in project management
curl -X POST "https://jira.local/rest/api/2/issue" \
  -H "Authorization: Bearer $JIRA_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{
    "fields": {
      "project": {"key": "SEC"},
      "summary": "Implement PAM for service accounts (IR-2024-042)",
      "issuetype": {"name": "Task"},
      "priority": {"name": "High"},
      "assignee": {"name": "security_engineer"},
      "duedate": "2024-03-15"
    }
  }'

Step 6: Update Playbooks and Detection Rules

yaml
# New Sigma detection rule based on incident learnings
title: Kerberoasting Activity Detected
status: stable
description: Detects Kerberoasting based on IR-2024-042 lessons
logsource:
  product: windows
  service: security
detection:
  selection:
    EventID: 4769
    TicketEncryptionType: '0x17'
  condition: selection
level: high
tags:
  - attack.credential_access
  - attack.t1558.003

Key Concepts

Concept Description
Blameless Post-Mortem Reviewing incidents focusing on systems, not blaming individuals
Root Cause Analysis Identifying the fundamental reason the incident occurred
5 Whys Iterative questioning technique to find root cause
MTTD Mean Time to Detect - time from compromise to detection
MTTC Mean Time to Contain - time from detection to containment
MTTR Mean Time to Recover - time from eradication to full recovery
Continuous Improvement Iterating on IR processes based on real incident data

Tools & Systems

Tool Purpose
TheHive/ServiceNow Incident timeline and documentation
Jira/Azure DevOps Action item tracking
Confluence/SharePoint Lessons learned documentation
Splunk/Elastic Incident metrics and detection improvement
Sigma Detection rule development

Common Scenarios

  1. Ransomware Post-Mortem: Review entire kill chain from initial access to encryption. Identify detection gaps and backup failures.
  2. Phishing Campaign Review: Analyze why users clicked, why email filters missed it, and how to improve training.
  3. Cloud Misconfiguration Incident: Review IaC pipeline, CSPM coverage, and change management process.
  4. Insider Threat Review: Examine DLP effectiveness, access control gaps, and user monitoring capabilities.
  5. Third-Party Breach Impact: Review vendor risk assessment process and data sharing agreements.

Output Format

  • Post-incident review meeting minutes
  • Root cause analysis document
  • Incident metrics report (MTTD, MTTC, MTTR)
  • Action items list with owners and deadlines
  • Updated IR playbooks and detection rules
  • Executive summary for leadership

Expand your agent's capabilities with these related and highly-rated skills.

mukul975/Anthropic-Cybersecurity-Skills

mapping-mitre-attack-techniques

Maps observed adversary behaviors, security alerts, and detection rules to MITRE ATT&CK techniques and sub-techniques to quantify detection coverage and guide control prioritization. Use when building an ATT&CK-based coverage heatmap, tagging SIEM alerts with technique IDs, aligning security controls to adversary playbooks, or reporting threat exposure to executives. Activates for requests involving ATT&CK Navigator, Sigma rules, MITRE D3FEND, or coverage gap analysis.

4,300 470
Explore
mukul975/Anthropic-Cybersecurity-Skills

hunting-for-spearphishing-indicators

Hunt for spearphishing campaign indicators across email logs, endpoint telemetry, and network data to detect targeted email attacks.

4,300 470
Explore
mukul975/Anthropic-Cybersecurity-Skills

analyzing-malicious-url-with-urlscan

URLScan.io is a free service for scanning and analyzing suspicious URLs. It captures screenshots, DOM content, HTTP transactions, JavaScript behavior, and network connections of web pages in an isolat

4,300 470
Explore
mukul975/Anthropic-Cybersecurity-Skills

implementing-zero-standing-privilege-with-cyberark

Deploy CyberArk Secure Cloud Access to eliminate standing privileges in hybrid and multi-cloud environments using just-in-time access with time, entitlement, and approval controls.

4,300 470
Explore
mukul975/Anthropic-Cybersecurity-Skills

implementing-pam-for-database-access

Deploy privileged access management for database systems including Oracle, SQL Server, PostgreSQL, and MySQL. Covers session proxy configuration, credential vaulting, query auditing, dynamic credentia

4,300 470
Explore
mukul975/Anthropic-Cybersecurity-Skills

detecting-t1003-credential-dumping-with-edr

Detect OS credential dumping techniques targeting LSASS memory, SAM database, NTDS.dit, and cached credentials using EDR telemetry, Sysmon process access monitoring, and Windows security event correlation.

4,300 470
Explore

Didn't find tool you were looking for?

Be as detailed as possible for better results