Uddip Ranjan

Harp6x's Personal website

Threat Intelligence Fundamentals: Building a CTI Program

Published on January 5, 2024

Introduction

Cyber Threat Intelligence (CTI) is the collection, analysis, and dissemination of information about cyber threats. A well-structured CTI program can significantly enhance an organization’s security posture by providing actionable insights into potential threats.

Types of Threat Intelligence

Strategic Intelligence

Tactical Intelligence

Operational Intelligence

Intelligence Lifecycle

1. Planning and Direction

Define intelligence requirements:

2. Collection

Gather information from multiple sources:

# Example: Threat feed collection
import requests
import json

def collect_threat_feeds():
    feeds = [
        "https://api.abuseipdb.com/api/v2/blacklist",
        "https://urlhaus.abuse.ch/downloads/csv/",
        "https://raw.githubusercontent.com/firehol/blocklist-ipsets/master/firehol_level1.netset"
    ]
    
    for feed in feeds:
        response = requests.get(feed)
        if response.status_code == 200:
            process_feed_data(response.text)

3. Processing

Transform raw data into structured intelligence:

4. Analysis

Apply analytical techniques:

5. Dissemination

Share intelligence with stakeholders:

Intelligence Sources

Open Source Intelligence (OSINT)

Commercial Intelligence

Internal Intelligence

Intelligence Tools and Platforms

Open Source Tools

# MISP - Threat intelligence sharing
git clone https://github.com/MISP/MISP.git
cd MISP
./INSTALL/INSTALL.sh

# YARA - Pattern matching
pip install yara-python

# TheHive - Case management
docker run -d -p 9000:9000 thehive4/thehive4

Commercial Platforms

Intelligence Analysis Techniques

Threat Modeling

graph TD
    A[Threat Actor] --> B[Capabilities]
    B --> C[Motivations]
    C --> D[Targets]
    D --> E[Attack Vectors]
    E --> F[Impact Assessment]

Indicator Analysis

Trend Analysis

Intelligence Products

Daily Threat Briefs

Weekly Intelligence Reports

Monthly Executive Summaries

Integration with Security Operations

SIEM Integration

# Example: SIEM alert enrichment
def enrich_alert_with_intel(alert):
    iocs = get_relevant_iocs(alert)
    threat_actors = get_attribution(iocs)
    ttp = get_ttp_mapping(alert)
    
    return {
        'alert': alert,
        'intelligence': {
            'iocs': iocs,
            'threat_actors': threat_actors,
            'ttp': ttp,
            'risk_score': calculate_risk_score(iocs, threat_actors)
        }
    }

Incident Response

Threat Hunting

Best Practices

  1. Define clear requirements: Understand what intelligence is needed and why
  2. Use multiple sources: Don’t rely on a single intelligence source
  3. Validate information: Verify intelligence before acting on it
  4. Share intelligence: Contribute to the broader security community
  5. Measure effectiveness: Track how intelligence improves security outcomes
  6. Automate where possible: Use tools to process and disseminate intelligence
  7. Maintain context: Understand the broader threat landscape

Challenges and Solutions

Common Challenges

Solutions

Conclusion

Effective threat intelligence requires a structured approach, the right tools, and continuous refinement. The goal is to transform raw threat data into actionable intelligence that enhances security decision-making and incident response capabilities.

Remember: Intelligence is only valuable if it’s actionable, timely, and relevant to your organization’s specific needs.


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