DEV Community: Bernie

Purple Teaming, Or: Why Siloed Teams Fail

Bernie — Mon, 02 Feb 2026 06:32:11 +0000

In my last blog post, we got into the high-stakes world of Red Teams vs. Blue Teams. You’ve got the “ghosts” in the machine (the Red Team) trying to slip through the cracks, and the defenders (the Blue Team) watching every log like a hawk.

It sounds incredibly cool on paper. But in a real world scenario, this competitive setup can lead to some pretty big headaches. Consider: a Red Team might spend months building a custom exploit, successfully storm the gates of a database, and then drop a 200-page PDF report on someone's desk. Meanwhile, the Blue Team is drowning in 10,000 alerts every single day. That report? It’s probably going to sit at the bottom of an inbox for weeks.

By the time anyone actually opens it, the "attack" is ancient history. The company isn't any safer; they've just paid for a very expensive digital paperweight. This is what happens when teams work in silos. It’s a game where everyone loses because nobody is playing on the same board.

Why keeping the spear and shield separate is a mistake

When offensive and defensive teams live in totally different corners of the office, things can get messy fast, and things usually break down in three specific ways:

1. The Information Gap

The Red Team often feels like they have to "win" by staying hidden. While that’s fine for a one-off stealth test, it doesn’t actually help the company get better. If the Blue Team doesn’t know what was tested, they don’t know what to fix. It turns into a game of hide-and-seek where the seeker is wearing a blindfold.

2. The "Gotcha" Culture

There’s often a weird tension between the two sides. The Red Team gets a "win" for breaking things, and the Blue Team feels like they "lost" because they missed it. This creates a toxic culture where people care more about looking smart than they do about actually stopping attackers. Security should be a team sport, not an ego contest.

3. The "Reports" Graveyard

The report-centric model is broken. If you find a hole in the fence on Monday, you should probably fix it on Monday. Waiting for a "final debrief" weeks later is like leaving your front door wide open while it’s pouring rain outside.

The Purple Solution: Collaboration Over Competition

This is where the Purple Team concept comes in. It’s not necessarily about hiring a whole new department. It’s mostly about a change in mindset.

In a Purple Team setup, the walls come down. The Red Team doesn’t just "attack": instead, they emulate. They’ll actually sit down with the Blue Team and say, "Hey, we're going to try a password spray against the staging server at 2:05 PM today. We’re using this specific tool. Can you check if your alerts actually catch it?"

If the Blue Team doesn't see anything, the Red Team doesn't cheer. They pause. They show the Blue Team exactly what they did, line by line. They dig into the logs together and realize, "Wait, our log aggregator is ignoring failed logins from this subnet." They fix the rule, run it again, and bam, the alert triggers. That is the magic of working together. You just closed a security gap in 20 minutes that might have taken 20 weeks in that old siloed model.

To really see how this works, we need to move away from "attack scripts" vs "defense scripts" and start thinking about integrated verification.

A Purple Team script does not just launch an attack and walk away: it checks the results from both sides immediately. Here is a quick Node.js example of what that looks like. We are going to simulate an unauthorized port scan and then check our (mocked) logs to see if the system actually flagged it.

/*
 * PURPLE TEAMING EXERCISE
 * We're testing if our system correctly logs unauthorized
 * connection attempts to Port 8080.
 */

const net = require("net");

// Configuration for our simulation
const TARGET_IP = "127.0.0.1";
const HONEY_PORT = 8080;
const SIMULATION_NAME = "Exercise: Restricted Service Access";

/**
 * [RED TEAM]
 * This function mimics an unauthorized user poking at a restricted service.
 */
async function emulateUnauthorizedAccess() {
  return new Promise((resolve) => {
    console.log(
      `[RED] Emulating connection attempt to restricted port ${HONEY_PORT}...`,
    );

    const socket = new net.Socket();
    socket.setTimeout(1000); // Quick attempt

    socket.on("connect", () => {
      console.log(`[RED] Connection established. (Expected for a probe)`);
      socket.destroy();
      resolve(true);
    });

    socket.on("error", (err) => {
      console.log(`[RED] Connection failed: ${err.message}`);
      resolve(false);
    });

    socket.on("timeout", () => {
      console.log(`[RED] Connection timed out.`);
      socket.destroy();
      resolve(false);
    });

    socket.connect(HONEY_PORT, TARGET_IP);
  });
}

/**
 * [BLUE TEAM]
 * This queries our detection logs.
 */
async function verifyDetection(probeTime) {
  console.log(
    `[BLUE] Reviewing SIEM logs for activity at ${probeTime.toLocaleTimeString()}...`,
  );

  // Simulating a minor delay for log ingestion
  await new Promise((r) => setTimeout(r, 500));

  // MOCK LOG SEARCH: In a real test, you'd check for the RED TEAM's IP address
  const mockLogs = [
    {
      host: "127.0.0.1",
      port: 8080,
      timestamp: probeTime,
      msg: "ALERT: Potential Reconnaissance detected!",
    },
  ];

  const findMatch = mockLogs.find((log) => log.port === HONEY_PORT);
  return findMatch ? findMatch.msg : null;
}

/**
 * [PURPLE TEAM]
 * This is the bridge that ties everything together. The attack is run,
 * then immediately the detection logic is checked.
 */
async function executePurpleExercise() {
  console.log(`\n=== Starting ${SIMULATION_NAME} ===`);
  const startTimeNode = new Date();

  // 1. Launch the attack
  const wasSuccessfulProbe = await emulateUnauthorizedAccess();

  if (!wasSuccessfulProbe) {
    console.log(
      "[PURPLE] ACTION REQUIRED: The 'attack' didn't even reach the target. Check network connectivity.",
    );
    return;
  }

  // 2. Immediately verify if the Blue Team's logic caught it
  console.log("\n[PURPLE] Moving to Verification Phase...");
  const detectionMessage = await verifyDetection(startTimeNode);

  if (detectionMessage) {
    console.log(`[PURPLE] ✅ SUCCESS: Detection logic is functional.`);
    console.log(`[PURPLE] Log Detail: "${detectionMessage}"`);
  } else {
    console.log(
      `[PURPLE] ❌ FAILURE: The attack was successful, but NO detection was found.`,
    );
    console.log(
      `[PURPLE] Remediation: Update Port 8080 monitoring rules to alert on incoming SYNs.`,
    );
  }

  console.log(`=== ${SIMULATION_NAME} Complete ===\n`);
}

executePurpleExercise();

How this helps your career

If you're just starting out in security or dev work, understanding this bridge is your "superpower." Companies don't just want hackers who can break things, and they don't just want analysts who can stare at a screen. They want people who can build systems. Systems that are tested, verified, and always improving.

When you start thinking in Purple, you stop being just another resource and start being a security architect. You're building the feedback loops that actually keep an organization safe.

Final Thoughts

Security isn't a final destination. It’s a constant state of evolution. By breaking down the walls between Red and Blue teams, we turn our defense from a stagnant wall into a living, breathing immune system.

It takes some effort to let go of the "us vs. them" ego, but the result is a safer environment for everyone. Good luck on your journey, and remember: aim to be at least 1% better today than you were yesterday!

Resources and Citations

CrowdStrike: What is Purple Teaming?
Rapid7: What is a Purple Team?
SentinelOne: Purple Teaming Definition
MITRE ATT&CK: Purple Teaming Fundamentals

Corporate Wargames: Red Teams vs Blue Teams

Bernie — Mon, 26 Jan 2026 07:03:31 +0000

If you are new to the world of cybersecurity, you have probably heard people talking about "Red Teams" and "Blue Teams." When I first heard these terms, I honestly pictured a massive game of Halo or Team Fortress 2. And surprisingly, that mental image is not actually that far off.

The best way to see if your fortress is secure is to try and storm the gates. That is the core idea behind these two teams. So today, I am going to break down exactly who these teams are, what they do, and why they are so important for keeping our data safe.

Part 1: The Red Team (The Attackers)

Think of the Red Team as the "bad guys," but the kind you actually want on your payroll. These are the ethical hackers. Their whole job is to act like a real-world attacker and try to break into the organization.

A normal penetration tester might just look for bugs in one specific app. But a Red Team? They go big. They run full simulations that test everything. They utilize social engineering, try to sneak into physical office buildings, and write custom malware to get past defenses.

Their goal is simple. They want to see how far they can get once they slip inside the walls.

Tech Spotlight: Reconnaissance
Before they launch an attack, a Red Team needs to find an open door. They often write scripts to scan for these weak points. Here is a simple Node.js script someone might use to scan for open ports on a server:

const net = require('net');
const target = '192.168.1.10';
const scanPort = (port) => {
  const socket = new net.Socket();
  socket.setTimeout(2000);
  socket.on('connect', () => {
    console.log(`[+] Port ${port} is OPEN`);
    socket.destroy();
  });
  socket.on('timeout', () => {
    socket.destroy();
  });
  socket.on('error', (err) => {
    socket.destroy();
  });
  socket.connect(port, target);
};
// Scan common ports
[21, 22, 80, 443, 3389].forEach(scanPort);

Part 2: The Blue Team (The Defenders)

If the Red Team is the spear, the Blue Team is the shield. These are the internal security staff who watch the organization's infrastructure day in and day out.

For a Blue Teamer, the job is all about vigilance. They analyze traffic logs, patch security bugs, and react to alarms. They are constantly looking for the subtle weirdness that indicates a Red Team (or a real criminal) is poking around. When they spot something, they jump into action to contain the threat and kick the intruder out.

Tech Spotlight: Detection
To catch that Red Team port scan we just talked about, a Blue Teamer might create a simple listener or "honeypot" to detect unauthorized access. Here is a Node.js script that acts as a trap. It listens on a sensitive port and logs an alert if anyone tries to connect:

const net = require('net');
const server = net.createServer((socket) => {
  const remoteAddress = socket.remoteAddress;
  console.log(`ALERT: Suspicious connection attempt from ${remoteAddress} on port 22!`);
  // Log this incident for further investigation
});
server.listen(22, () => {
   console.log('Honey port active. Watching for intruders...');
});

Part 3: Purple Teaming (Working Together)

For a long time, these teams stayed in their own corners. Red Teams would attack and leave a report. Blue Teams would read it and scramble to fix things. It was competitive, and sometimes it caused friction.

That is where the Purple Team concept comes in. It is not always a separate team of people. It is more of a mindset where Red and Blue work side by side.

The Red Team launches an attack and tells the Blue Team immediately.
The Blue Team checks if their tools saw it.
If they missed it, the Red Team shows them exactly how to catch it next time.
This makes everyone better, faster.

Conclusion

The push and pull between Red and Blue teams is what drives modern cybersecurity. The Red Team exposes where you are weak, and the Blue Team builds the resilience you need to survive.

I hope this guide helped clarify the difference between these two critical roles. Whether you want to be the one breaking in or the one keeping them out, there is a place for you in this field. Good luck on your journey, and remember to aim to be at least 1% better today than you were yesterday!

Resources and Citations

CrowdStrike. (2025). Red Team vs. Blue Team: What’s the Difference? CrowdStrike
IBM. (2025). What is Red Teaming? IBM
NIST. (2025). Glossary: Red Team. National Institute of Standards and Technology. NIST Red Team
NIST. (2025). Glossary: Blue Team. National Institute of Standards and Technology. NIST Blue Team

A newbie's guide to professional hackers

Bernie — Mon, 19 Jan 2026 09:02:05 +0000

The term "hacker" used to conjure images of a dark room dimly lit by a computer screen, with a person hunched over a keyboard typing furiously as text flies through their screen. Of course, the reality is very different these days, and professional hackers come in a variety of different types.

Black Hat Hackers

This is the type of hackers you might think of as a "classic" hacker. These are the people who take their knowledge and skills and use it for personal gain. Whether that personal gain is monetary, fame, or something else is largely dependent on the individual black hat as they often have a myriad of reasons for their actions. Pretty much any time you hear about a hack on the news, you can assume a black hat was involved.

White Hat Hackers

On the opposite end of the ethical spectrum are white hat hackers. These are individuals who look for hacks or exploits in systems that they have explicit permission to try and hack. While this may seem counterintuitive (why would a company want someone to try and break into their system?), it's actually a very effective method of system hardening. By identifying vulnerabilities and addressing them, these kinds of hackers work to make the systems we use every day less susceptible to bad actors who would otherwise compromise them.

Grey Hat Hackers

Grey hat hackers are neither malicious like black hats nor are they benevolent like white hats. While white hats will get explicit permission or even be employed by a company to break into a system, and black hats will break into any system for personal gain, grey hats usually have a different motivation. Whether it be genuine curiosity, boredom, or just because they think they can, grey hat hackers will look for vulnerabilities in systems but instead of exploiting them for personal gain, they often try to report their findings to the administrators of the systems. This is why grey hat findings tend to be controversial as they are usually admitting they broke the law when they report their findings. Still they serve as an important part of the security ecosystems as grey hats have been responsible for finding some very serious potential zero day bugs.

Conclusion

The field of professional hacking is changing rapidly. In the not too distant past, hackers were seen as a universal scourge for large companies. A perpetual shadow that could bring a storm at any moment without warning. Today, most companies see the value of finding the flaws in their systems before someone else does and employ their own teams of hackers to ensure that the systems you and I rely on every day operate smoothly and as intended. This evolution has shifted cybersecurity from one of reactive defense to one of proactive protection. So the next time you swipe your credit card without fear of your information being stolen, thank your local hacker!

Git for newbies(from a newbie)

Bernie — Fri, 12 Dec 2025 07:29:21 +0000

Cover Image Credit: https://github.com/GIT

Intro to Git:

For me, Git was always one of those things I heard talked about, but never really had to deal with until I started my journey to become a programmer. Once I was introduced to it, it felt like having to learn a new language and most of the tutorials I found seemed geared towards more experienced users. So today, I’m going to try and break down the basics of Git and introduce you to the concept of collaborative coding. It’s a powerful tool, and learning Git will be incredibly useful for any developer, no matter what you’re building. I won't be going over very many command examples in this post, but will instead try to break down the concepts in a way that will make more advanced guides easier to understand.

Part 1: Git fundamentals

The way I like to think about Git is that it’s like a save point for your code, just like in a video game. If you make a mistake in a game, but you have a save point before it happened, you can reload and go back to that exact moment. Git works on a similar concept, but instead of save points, it uses things called commits.

Part 1.1: Repositories and Saving code

You’ve probably heard the word “repository” mentioned in relation to code, but it might not be immediately clear what it is. Simply put, a repository is a container that tracks every change made to your code over time. Those changes can be made by you, or by anyone you invite to collaborate on the project. Repositories are the foundation of Git’s commit system as it allows you to see exactly what your code looked like at any point in its history. If you’re just starting out, the benefit of this might not be obvious, but as you collaborate more, you’ll quickly realize how invaluable it is to be able to look back at clean examples of previous code states. It’s not just about fixing mistakes though, it’s also helpful for understanding why certain decisions were made and tracking the evolution of your project.

Part 1.2: Pushing and Pulling

Another fundamental part of the Git workflow is the idea of "pushing" and "pulling" code. This is how we keep our repositories synchronized. Whether it’s updating the central repository with new code we’ve written locally, or updating our local code with changes made by collaborators. When someone says they "pushed" their code, it means they’ve uploaded their latest changes to the repository. Conversely, "pulling" code is the act of downloading those changes and integrating them into your local codebase. Going back to our save point analogy, pushing is like "saving" your game progress, and pulling is like "loading" a saved game.

Part 2: Collaborative Coding

Now that we have a general idea of repositories and how to update code, both pushing changes and pulling from others; it’s time to look at remotes in Git. Remotes can be a little tricky when you’re first starting out, as Git has powerful merging functions that might not make a lot of sense right away, and that’s perfectly okay! Don’t worry about mastering those advanced features just yet. For now, it’s enough to understand that a remote is simply a version of your repository that lives somewhere else, usually on a platform like GitHub, GitLab, or Bitbucket. This allows you to collaborate with others, back up your code, and access it from different computers.

Part 2.1: Git Remotes

The key thing to understand about remote repositories in Git is that Git considers any repository not on your local machine to be a remote. This means it doesn’t matter if you’re pulling from a website like GitHub or from another computer on your local network, Git needs to know where to find it. Thankfully, Git makes it very easy to add and update these remote locations. You essentially tell Git the address of the remote repository, and it handles the connection for you. This allows you to seamlessly push and pull changes, regardless of where the remote repository is hosted.

Part 2.2: Remote Naming Conventions

When you’re starting out as a developer, you’ll often be copying projects from other people (a process called cloning) to your local machine. If you use Git for this, it automatically sets up your first remote, usually named “origin”. You can see a list of any remotes associated with your project by navigating to it in your terminal and running the command `git remote -v`. Here, `git remote` tells Git to list the remotes, and the "-v" flag provides more detailed output, showing the remote’s location (usually a URL). While “origin” typically points to the original repository you cloned from, you can rename it if you wish. However, it’s generally best to stick with the default name, as most guides and tutorials will assume your remote is called “origin”. Knowing this default will save you confusion down the line, and it’s worth noting you can have multiple remotes associated with a single project if needed.

Conclusion:

We’ve now covered the basics of Git and broken down the core concepts to hopefully give you a better understanding of how the process works. The best way to truly learn Git is to use it. Find a project online, fork it, and clone it locally. Then, make changes to the code and try pushing them. Even better, have a friend fork and clone the same repository and make different changes. Experiment with adding their repository as a remote and pulling their changes into your code. This is a great way to see Git’s merging capabilities in action! Git gives you incredibly precise control over your code, and it can seem daunting at first. But mastering these basic concepts will make learning the more advanced features much easier down the road. Good luck on your journey and remember to aim to be at least 1% better today than you were yesterday. Every step forward counts on the path to becoming a more competent developer.