Welcome to the first post in our new series focused on Digital Forensics and Incident Response (DFIR). In this journey, we’ll explore how and why these measures come into play, how defenders can proactively mitigate threats before they escalate, and what the investigation process truly looks like—from the ground up.

We’ll walk through every step, from threat hunting to malware analysis—both static and dynamic—while weaving in powerful frameworks like the MITRE ATT&CK Matrix and Lockheed Martin’s Cyber Kill Chain to illuminate how attackers operate and how we, as defenders, can stay ahead.

Today, we begin where every intrusion starts: Reconnaissance.

🔍 What is Reconnaissance?

Reconnaissance is the information-gathering phase where attackers scout their targets to identify weaknesses. This can involve everything from passive monitoring to active probing of systems. The data collected here shapes their entire attack strategy.

MITRE Technique: T1595 – Active Scanning

MITRE Technique: T1592 – Gather Victim Identity Information

🧠 Proactive Countermeasures: Threat Hunting & Threat Intelligence

🔎 Threat Hunting

Threat hunting is the proactive search for signs of adversary activity—even before alerts are triggered. Analysts monitor logs, DNS, endpoints, and behavior patterns to detect:

• Low-and-slow port scans
• Enumeration attempts
• Malicious web app fingerprinting

🌐 Threat Intelligence

Threat intelligence helps enrich detections with context by integrating external feeds into your SOC tools. These feeds provide:

• Known malicious IPs and scanner signatures
• Suspicious DNS behaviors
• Behavioral trends and threat actor TTPs

🛠️ Tools Used by Attackers in Recon

Passive Reconnaissance Tools:

• Shodan – Exposed device search engine
• theHarvester – Email, subdomain, and user enumeration
• Maltego – Visual link analysis and OSINT
• Google Dorking – Index-based data discovery

Active Reconnaissance Tools:

• Nmap – Port scanning and service detection
• Recon-ng – Modular web recon framework
• DNSenum / Fierce – DNS and subdomain enumeration
• Netcat – Lightweight port listener and scanner

🛡️ How to Mitigate Reconnaissance

1. Leverage Threat Intelligence & Hunting

• Use threat feeds (AlienVault OTX, GreyNoise) to block known scanners
• Deploy honeypots (T-Pot, Honeyd) to detect early scanning
• Correlate behavior across endpoints, logs, and DNS

2. Minimize Public Exposure

• Audit your public assets using Shodan Monitor or SecurityTrails
• Close unnecessary ports and services on perimeter systems
• Use Cloudflare or CDNs to mask infrastructure

3. Harden DNS & Email Infrastructure

• Disable DNS zone transfers
• Use split-horizon DNS
• Mask or obfuscate email addresses on public sites

4. Detect & Block Scanning Behavior

• Deploy IDS/IPS (e.g., Suricata, Snort) with recon signatures
• Enable geo-fencing and rate limiting on exposed APIs
• Use fail2ban and CrowdSec for behavioral blocking

5. Scrub Metadata & Avoid Leakages

• Use tools like mat2 or ExifTool to remove document metadata
• Prevent backend disclosure in web responses
• Ensure code repos don’t leak API keys or configurations

🚨 Why It Matters for DFIR

Reconnaissance often precedes every major breach. If left unnoticed, it provides attackers with a roadmap into your environment. Understanding and interrupting this phase allows defenders to respond before damage is done.

DFIR professionals must identify whether recon was conducted and how—using logs, threat intel, and behavioral patterns to trace back the attack timeline and block repeat attempts.

🔜 What’s Next?

In the next post, we’ll move into Weaponization, where attackers turn gathered information into malware payloads. We’ll explore how to detect the creation and deployment of exploits—and how defenders can get ahead of them using sandboxing and behavioral analytics.

Until then, monitor your perimeter, enrich your intelligence, and hunt threats like your network depends on it…because it does.