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Introduction:
The journey from cybersecurity enthusiast to paid bug bounty hunter is a coveted path, filled with duplicated reports and informative closures. This article deconstructs the key technical and strategic lessons from a recent first bounty success on HackerOne, providing a roadmap for aspiring hunters to transform their skills into tangible rewards.
Learning Objectives:
- Understand the core methodologies for effective reconnaissance and target selection.
- Master the essential command-line tools for modern web application penetration testing.
- Develop a structured process for validating, exploiting, and reporting vulnerabilities to maximize payout potential.
You Should Know:
- The Art of Passive Reconnaissance with Subfinder and Amass
Before a single packet is sent, successful hunters map their target’s digital footprint. Passive reconnaissance gathers information without directly interacting with the target, minimizing detection risk.
`subfinder -dL targets.txt -o subdomains.txt`
`amass enum -passive -df targets.txt -o amass_subs.txt`
Step-by-step guide:
- Create a file `targets.txt` listing your target domains (e.g.,
example.com). - Run `subfinder` to discover subdomains using numerous public data sources and APIs, saving the results to
subdomains.txt. - Run `amass` in passive mode to correlate additional subdomains from its vast database of certificates, DNS, and archives.
- Combine, sort, and deduplicate the results:
cat subdomains.txt amass_subs.txt | sort -u > final_subs.txt. This consolidated list is your initial attack surface. -
Probing for Live Hosts and HTTP Services with HTTPX
Not all discovered subdomains are active. Filtering for live hosts and identifying web technologies is crucial for prioritization.
`httpx -l final_subs.txt -title -status-code -tech-detect -o live_targets.txt`
Step-by-step guide:
- Feed your list of subdomains (
final_subs.txt) intohttpx. - The tool will probe each subdomain to see if it’s alive.
- The flags
-title,-status-code, and `-tech-detect` will extract the page title, HTTP status code (e.g., 200, 404), and technologies used (e.g., PHP, React, Nginx). - The output file `live_targets.txt` now contains a curated list of active web applications to focus on, saving you from wasting time on dead endpoints.
3. Automated Vulnerability Scanning with Nuclei
While manual testing is key, automated scanners can help identify low-hanging fruit and common misconfigurations at scale.
`nuclei -l live_targets.txt -t /path/to/nuclei-templates/ -o nuclei_scan_results.txt`
Step-by-step guide:
- Ensure you have the community-driven `nuclei-templates` repository cloned locally.
- Run `nuclei` with the `-l` flag pointing to your `live_targets.txt` file.
- Nuclei will run thousands of predefined vulnerability tests against all live hosts.
- Review the `nuclei_scan_results.txt` file carefully. Triage any findings, especially for “info” or “low” severity issues that might be overlooked and could be part of a more significant chain attack.
4. Manual Testing for Access Control Flaws (IDOR)
Automated tools miss logic flaws. Insecure Direct Object Reference (IDOR) is a classic vulnerability where user-controlled input is used to access objects without authorization checks.
Step-by-step guide:
- Log into an application with two different user accounts (e.g., `userA` and
userB). - As
userA, navigate to a page that displays private data, such as `https://app.com/profile/view?user_id=12345`. - Change the `user_id` parameter in the URL or POST request to
userB‘s ID (e.g.,67890). - If the application displays
userB‘s private profile data touserA, you have successfully identified a critical IDOR vulnerability. Report this immediately.
5. Testing for JWT Vulnerabilities
JSON Web Tokens (JWTs) are common for authentication. Misconfigurations can lead to severe privilege escalation.
`python3 jwt_tool.py -C -d /path/to/wordlist.txt`
Step-by-step guide:
- Intercept a web request with Burp Suite and find the JWT in the `Authorization: Bearer` header.
- Use a tool like `jwt_tool` to analyze the token.
- The `-C` flag runs multiple checks: testing if the algorithm can be changed to “none”, verifying the token’s validity, and checking for kid header path traversal.
- The `-d` flag enables a brute-force attack against weak HS256 secrets. A successful crack allows you to forge valid tokens for any user.
6. Cross-Site Scripting (XSS) Payload Crafting and Proof-of-Concept
XSS remains a staple finding. Crafting a working proof-of-concept (PoC) is essential for a valid report.
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Step-by-step guide:
- Identify a reflection point, such as a search parameter:
search?q=test. - Inject a basic payload like
<svg onload=alert(1)>. If an alert box pops up, you have confirmed XSS. - For a more impactful report, use a blind XSS payload that sends a victim’s cookie to a server you control (e.g., a Burp Collaborator domain).
- Replace `your-collab-server` with your domain. This demonstrates the concrete risk of session hijacking.
7. Crafting the Perfect Bug Bounty Report
A well-written report is as important as the finding itself. It must be clear, concise, and demonstrate impact.
Step-by-step guide:
- Clear and specific (e.g., “IDOR allows viewing of any user’s full credit card details via
/api/v1/orders/[bash]“). - Summary: Briefly describe the vulnerability type and affected endpoint.
- Steps to Reproduce: Numbered, detailed, and傻瓜-proof steps for the triager to follow. Include exact URLs, request/response pairs (in code blocks), and payloads used.
- Impact: Clearly state the business impact. Does it lead to data breach, account takeover, financial loss? Quantify if possible.
- Remediation: Suggest a fix (e.g., “Implement proper authorization checks on the backend that verify the user owns the requested resource ID”).
What Undercode Say:
- Persistence Over Genius: This success story underscores that consistent effort, learning from duplicates, and community engagement are more critical than innate skill for breaking into bug bounties.
- The Toolchain is Essential, But Context is King: Mastering a modern recon and testing toolkit (Subfinder, Amass, HTTPX, Nuclei) is non-negotiable for efficiency. However, the highest-value bugs are found through manual, intelligent analysis of the application’s unique logic, not just automated scanning.
- The analysis reveals a mature approach to the field. The hunter emphasizes the grind of initial failures (duplicates, informatives) as a learning tool, not a deterrent. Furthermore, acknowledging a support network of mentors and peers highlights a often-overlooked aspect of success in cybersecurity: collaboration. This mindset of continuous learning, tool mastery, and community involvement is the true blueprint for replicating this $750 success.
Prediction:
The barrier to entry for effective bug hunting will continue to lower as open-source tools become more powerful and integrated. This will lead to a massive increase in crowd-sourced security researchers, forcing organizations to adopt more sophisticated triage and automation on their end. Platforms will increasingly prioritize AI-assisted duplicate detection and severity classification. Consequently, hunters who focus on complex, logic-based vulnerabilities that machines cannot easily find will thrive, while those reliant solely on automated scans will see their yields diminish.
🎯Let’s Practice For Free:
IT/Security Reporter URL:
Reported By: Mohamadaxel Cybersecurity – Hackers Feeds
Extra Hub: Undercode MoN
Basic Verification: Pass ✅
