When it comes to cybersecurity, the most valuable information isn’t always hidden behind locked doors. Sometimes, it’s right out in the open, waiting for someone to notice. That’s where OSINT, or Open Source Intelligence, comes in. It’s all about gathering and analyzing publicly available data to uncover risks, track threats, or simply understand how exposed an organization might be.

I’ve been working on a personal OSINT project that combines PowerShell scripting with API calls to pull detailed intelligence on domains. The experience has been eye opening. There’s so much information out there, and with a little automation, you can turn hours of manual searching into a streamlined process that delivers actionable insights in seconds.

What Is OSINT, Really?

OSINT stands for Open-Source Intelligence. It refers to the process of collecting and analyzing data that is publicly accessible, including anything from domain registration records and SSL configurations to leaked passwords and exposed devices. OSINT isn’t just about running a quick Google search; it’s a methodical approach to collecting and connecting data points from public sources. Think domain registration records, SSL certificate details, leaked credentials, and even exposed servers. The best part? It’s completely legal because everything is publicly accessible.

In cybersecurity, OSINT is like detective work. You’re piecing together clues that others might overlook. A misconfigured server here, an old email address tied to a data breach there. Individually, these details might seem insignificant, but together, they can reveal vulnerabilities or even help track malicious activity.

The Project: OSINT Scripting with PowerShell and APIs

Instead of relying on pre built tools, I decided to build my own script from scratch. Using PowerShell, I connected to multiple OSINT APIs to gather intelligence on domains. Here’s a breakdown of the tools I used and what they do:

• Qualys SSL Labs API: This API provides detailed SSL and TLS configuration data for any domain. It flags weak encryption, outdated protocols, and other security issues. You’d be surprised how many sites still use outdated certificates.
• Hunter.io API: This tool helps find email addresses associated with a domain. It’s useful for mapping out an organization’s structure or identifying potential targets for phishing campaigns.
• Shodan API: Shodan scans the internet for connected devices. With this API, I can find IP addresses, open ports, and services linked to a domain. It’s shocking how many unsecured databases and servers are just sitting out in the open.
• AlienVault OTX: This threat intelligence platform pulls data on malware, suspicious IPs, and other malicious activity tied to a domain. If a domain has a history of bad behavior, OTX will usually know about it.
• DeHashed: This service searches through data breaches for leaked credentials. If an email address or password linked to a domain has been compromised, DeHashed can find it.

By scripting these API calls in PowerShell, I’ve been able to automate the entire process. The script pulls data from each source, organizes it, and spits out a clean report. It’s not just about saving time. It’s about understanding how to turn raw data into meaningful insights.

Why This Matters

If I can automate this, so can attackers. That’s why OSINT is such a critical part of cybersecurity. Organizations often don’t realize how much information they’re exposing. Forgotten subdomains, misconfigured cloud storage, reused passwords from old breaches. These are all low hanging fruit for anyone who knows where to look.

Working on this project has been equal parts fascinating and alarming. Fascinating because of how much you can learn with just a domain name and some scripting. Alarming because of how many vulnerabilities are just sitting there, waiting to be discovered.

This is why every security team should be running these same checks on their own domains. Not just annually, but continuously. The digital landscape changes daily - new subdomains get spun up, certificates expire, employees reuse compromised credentials. What was secure yesterday might be exposed today. Automated OSINT monitoring isn't just helpful for threat hunting; it's becoming essential for basic cyber hygiene.

The most sobering realization? Many organizations only discover these exposures after they've been exploited. By then, it's too late. Proactive OSINT work flips this script - it's about finding your weak spots before the attackers do. That's the difference between reading about a breach in the news and preventing one from happening in the first place.