What’s The Worst That Could Happen? These Security Mistakes Nearly Showed Me

Most security breaches don’t start with elite hackers in hoodies. They usually start with something small.

I’ve been in the room when minor mistakes nearly killed big projects. I’ve even made a few of them myself. If you’re building a startup or shipping your MVP, one slight misstep can undo everything you’ve worked for.

This article breaks down factual security mistakes I've seen and made that almost wrecked entire projects.

I’m sharing them so you don’t have to learn the hard way.

Let’s jump in.

Trusting Every Plugin, Package, and API

Assuming every library or API is safe is the easiest way to get hacked. Not everything online is secure.

Someone on Reddit recently shared how he got “API scammed.” A scammer pretended to be from Steam (a gaming platform) and told him to send his items to a “friend” or risk losing them. But the scammer changed the trade at the last second, and everything disappeared.

And it’s not just gamers. The moment you plug something into your database, browser, or backend, you’re handing over access.

In 2021, a popular npm package (ua-parser-js) used by thousands of developers every day was compromised. Hackers injected malware that stole passwords and mined cryptocurrency silently.

Open-source isn’t always 100% secure. APIs change. Some get deprecated, others start logging more than they should. So here’s what you should do to stay safe:

• Don’t install plugins or tools just because they’re popular.
• Stick to libraries from trusted sources.
• Use scanners like Snyk or Socket to scan and audit tools before using them.
• Update your tools regularly. Outdated ones are easier to compromise.

Leaving Debug Mode On in Production

Let’s say you just finished testing your app, and everything is working fine. You’re so excited to ship that you push it to production.

But then, you made a mistake. You forgot to turn off debug mode.

Leaving debug mode on in production can expose database queries, environment variables, and sensitive data like API keys or tokens.

I once worked with a team on a project where Flask's debug mode was left on during launch. A user triggered an error and saw our complete directory structure and partial environment configuration. Luckily, no data was lost. But we had to audit security, rotate secrets, issue a hotfix, and notify users.

Here’s what you can do to avoid this mistake:

• Always turn off debug or verbose logging in production.
• Use deployment checklist and automation.
• Separate development and production configurations with a secret manager.

Even the Laravel community has warned to disable debug mode in production. I’d take that advice if I were you.

Discarding an Old Computer Without Wiping It

We had an old laptop with a cracked screen lying around. It hadn’t been used since we got a new one. So I tossed it.

I didn’t wipe the hard drive, I didn't even encrypt anything. I just boxed it up and left it in a corner near the trash. A week later, I realized it still had client records, invoices, browser logins, including bank access, and old Slack exports.

If someone had plugged it in, they could have easily pulled up sensitive data. I got lucky, but Morgan Stanley didn’t.

In 2020, Morgan Stanley agreed to pay $60 million to settle a class-action lawsuit after they failed to properly retire IT equipment. Not once, but twice.

In 2016, they decommissioned two data centers, but the unencrypted hardware (still loaded with customer data) was resold to unauthorized buyers. Then in 2019, they transferred more servers to a vendor. Roughly 15 million customers were affected.

Discarding or selling your old computers or devices without wiping them clean can lead to identity and data theft. So before you dispose that device:

• Wipe all the drive. Use tools like DBAN or built-in OS options.
• Encrypt your device so no one can read the data on it.
• Partner with certified e-waste services for secure destruction and proper disposal.

Copying and Pasting API keys into Public Repositories

API keys are like secret passwords between your apps and other services. If you paste these keys into public code, anyone can grab and abuse them.

Palo Alto’s Unit 42 scanned over 24,000 GitHub files and found 12,000+ exposed secrets, including API keys. Some keys even granted full admin access.

Treat your keys like the sensitive credentials they are. Don’t paste API keys, database passwords, or secrets directly into your code or share screenshots of code with keys visible.

Do these instead:

• Use secret managers like AWS Secrets Manager, Azure Key Vault, or HashiCorp Vault.
• Rotate your API keys regularly, especially after team changes or incidents.
• Use environmental variables (.env files) to keep your secrets out of your codebase.
• Use automated scanners like GitHub secret scanning to help scan and detect secrets in your repository.

Exposing Admin Panels

Last month, a security researcher hacked the infamous LockBit Ransomware’s site and leaked their admin panel.

Yes! Hackers got hacked. If they can get exposed, so can you.

Your admin dashboard is your system’s control room. Once it’s discoverable, it’s vulnerable.

ThreatNG explained how accidentally exposing your admin panels can let attackers slip in without breaking a sweat.

Here’s how to properly secure your admin panels:

• Use proxies to limit discovery.
• Don’t use an obvious path like /admin or /dashboard.
• Use IP allowlisting so only trusted IP addresses can reach those pages.
• Conduct regular scans and audits to find and remove forgotten or hidden panels before someone else does.

Hardcoding Your Secrets into Codebase

Hardcoding your API keys, tokens, passwords, etc. may seem easy. But what if your code ever goes public (or leaks)? Those secrets go with it.

One subcontractor uploaded source code with a hardcoded access key for Toyota’s data services. The repo was public for years, possibly giving access to 296,019 customer records.

Uber also faced the same thing after an attacker discovered hardcoded admin credentials in a PowerShell script.

Hardcoding secrets is one of the most ignored mistakes in cybersecurity.

Most of the time, they go unnoticed in development and are buried in configuration files or source code. However, they can give unauthorized access to critical systems without setting off alarms once exposed.

Here’s what you can do:

• Use secret management tools that store secrets safely and rotate them regularly.
• Scan your code automatically before pushing updates.

Sharing One Login Across the Whole Team

Sharing accounts or passwords with multiple people is a terrible idea. A mistake we make without thinking about the aftermath.

If something goes wrong, you don’t know who’s responsible. You also can’t tell who made changes or stole info. Shared credentials kill accountability. They also make it easier for attackers to move around undetected.

Instead of sharing one login, do these:

• Create personal accounts for each user, even if they’re on the same team.
• Enforce role-based access. Give users just what they need.
• Use a password manager to securely share only the credentials they need.

Using a Random USB Drive

Imagine you found a USB stick lying on the ground and plugged it into your computer just because you’re curious. Sounds harmless right? Until a virus hits you.

My friend did exactly that. She picked up an old USB stick, plugged it in without thinking, and boom! Her screen lit up with over 30 virus alerts.

Some hackers load USBs with malware and leave them where someone might pick them up out of curiosity. Once plugged in, the malware runs, compromising your system or stealing your data. Some can even give remote access to your device.

So you should be careful what USB you plug into your computer.

• Use USB port blockers or turn off auto-run features.
• Have endpoint protection that flags unauthorized access attempts.
• Use cloud storage instead. It's safer and easier to manage access.

Final Words

Security isn’t just a checklist. It’s a mindset.

I’ve made these mistakes. I’ve cleaned them up, and I've learned (sometimes the hard way) that a bit of caution early on saves you from chaos later.

What about you?

Have you ever made a security mistake that nearly cost you a project or your job? \n Drop a comment. I’d love to learn from yours too.