Purple Teaming, Or: Why Siloed Teams Fail

#cybersecurity #devops #infosec #security

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!