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Arina Cholee
Arina Cholee

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The Hacker’s Playbook vs. SafeLine WAF: Who Wins?

#websecurity #cybersecurity #waf #safeline

SQL Injection (SQLi) has been one of the oldest and most dangerous web vulnerabilities for decades. Despite its age, it’s still a massive risk in 2025. If your app talks to a database, you've probably worried about SQLi at some point.

To see how well a modern open-source Web Application Firewall (WAF) performs against SQLi, I decided to test SafeLine WAF. It promises to block SQLi and other common web attacks out of the box. But does it really deliver? Let's find out.

Setting Up a Vulnerable Target

For the test, I spun up DVWA (Damn Vulnerable Web Application), a purposely insecure PHP app that's perfect for practicing attacks. Here’s the vulnerable SQL query I found inside DVWA:

SELECT first_name, last_name FROM users WHERE user_id = '$id';
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When I input 1, it returns the first user from the database. But what happens if I input something malicious?

Simulating an SQL Injection Attack

I injected the following payload:

1' UNION SELECT 1, database() #
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And voilà, the page returned the current database name. That means DVWA was vulnerable. An attacker could easily dig deeper and compromise sensitive information.

Enter SafeLine WAF

Now, let's put SafeLine WAF to the test. Here's how I set it up quickly:

  1. Deploy SafeLine using Docker.
  2. Add your site as an upstream to SafeLine.
  3. Route traffic through SafeLine’s reverse proxy.

Once deployed, I tried the same SQL injection payload again:

1' UNION SELECT 1, database() #
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Result?

Blocked! SafeLine intercepted the malicious request and returned a generic error page instead of leaking sensitive database information.

Logs and Visibility

The beauty of SafeLine doesn’t just stop at blocking attacks. Inside the SafeLine dashboard, I could see the SQL Injection attempt logged in full detail:

This visibility is invaluable for developers—not only is the attack blocked, but you also get detailed logs about the attempted attack, helping you monitor and improve your security posture.

Why This Matters

For many dev teams, manually sanitizing every input or reviewing every query just isn’t feasible. That’s where a WAF like SafeLine comes in, adding an essential layer of protection:

  • Blocks zero-day payloads, even if your app has coding flaws.
  • Prevents automated scanners from mapping your site and discovering vulnerabilities.
  • Gives you monitoring and logs for all security events.

Even if your app isn’t 100% secure, a WAF gives you valuable time and protection against attacks.

Final Thoughts

SafeLine WAF is far from just “another firewall.” It’s:

  • Free & Open Source (no licensing required).
  • Developer-friendly (Docker/Kubernetes support, quick deploy).
  • Smart Detection (semantic analysis instead of just static regex rules).

For small teams, indie projects, or anyone running a web service in 2025, this is a serious security upgrade at zero cost.

🔗 Helpful Links

If you’re looking for an easy-to-deploy, no-cost solution to protect your app from web attacks in 2025, SafeLine WAF is definitely worth trying. It's fast, effective, and gives you peace of mind with minimal effort.

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