- by x32x01 ||
🚨 Spring Boot Actuator Misconfiguration: A Bug Worth $55,000+ 🚨
Sometimes the most valuable vulnerabilities are hiding in plain sight 👀
One of the best real-world examples is Spring Boot Actuator Misconfiguration - a mistake that has led to bug bounty payouts of $55,000 or more 💰
This issue happens more often than you think, especially when developers leave Actuator endpoints exposed to the public internet.
When misconfigured, these endpoints become a gold mine for bug bounty hunters 🎯
Common exposed paths include:
Hunters usually scan for:
But here’s the critical mistake ❌
They forget to secure
Inside this file you may find:
If accessible, the server will return a massive memory dump containing sensitive data 🚨
But attackers often try a simple encoding trick.
📌
This can confuse some WAFs and allow the request to pass while the backend still processes it normally.
⚠️ This bypass works more often than people expect.
Secure your Actuator endpoints, restrict access, and never expose them to the public internet 🚀
Happy hacking - ethically 😎
Sometimes the most valuable vulnerabilities are hiding in plain sight 👀
One of the best real-world examples is Spring Boot Actuator Misconfiguration - a mistake that has led to bug bounty payouts of $55,000 or more 💰
This issue happens more often than you think, especially when developers leave Actuator endpoints exposed to the public internet.
What Is Spring Boot Actuator and Why It’s Dangerous ⚠️
Spring Boot Actuator provides monitoring and management endpoints for applications.When misconfigured, these endpoints become a gold mine for bug bounty hunters 🎯
Common exposed paths include:
- /actuator
- /actuator/health
How Bug Bounty Hunters Find This Vulnerability 🔍
The first step is always endpoint discovery.Hunters usually scan for:
/actuator/actuator/info/actuator/env/actuator/heapdump
Why Heapdump Is the Real Nightmare 💣
Developers often try to protect secrets by redacting sensitive values in the/env endpoint.But here’s the critical mistake ❌
They forget to secure
/heapdump.What Happens with Heapdump?
The endpoint downloads a file that can be 100MB or more containing live server memory 🧠Inside this file you may find:
- Auth tokens
- API keys
- Database credentials
- Session data
- Sensitive user information
/env becomes useless if /heapdump is exposed.Example of a Dangerous Request 🧪
Code:
GET /actuator/heapdump HTTP/1.1
Host: vulnerable-site.comWAF Bypass Trick Using URL Encoding 🕶️
Sometimes a WAF (Web Application Firewall) blocks direct access to heapdump.But attackers often try a simple encoding trick.
The Trick 💡
Add an encoded # at the end of the path:/actuator/heapdump%23📌
%23 is the URL-encoded version of #This can confuse some WAFs and allow the request to pass while the backend still processes it normally.
⚠️ This bypass works more often than people expect.
Why This Bug Is So Valuable in Bug Bounty 💰
This vulnerability can lead to:- Full account takeover
- Internal system access
- Cloud credential leaks
- Complete infrastructure compromise
Key Takeaways for Pentesters and Bug Hunters 🧠
If you’re doing pentesting or bug bounty hunting:- Don’t stop at health checks
- Test all Actuator endpoints
- Always try URL encoding to bypass WAF rules
- Treat heapdump as critical severity
Final Lesson 📌
The vulnerability isn’t advanced hacking. It’s bad configuration.Secure your Actuator endpoints, restrict access, and never expose them to the public internet 🚀
Happy hacking - ethically 😎
