Vulnerabilities to Master in 2025: Your Path to $100k in Bug Bounties

bug bountyhacking
Written By Ben Sadeghipour

2025 is here, and if you’re serious about bug bounties, it’s time to kick off the year really strong. Last year, my entire focus was on helping beginners get started, breaking down the fundamentals, and making sure you had a solid foundation. And don’t worry—I’ll still keep putting out beginner-friendly content because I know new hackers join us every day.

But this year, we’re taking it to a whole different level. My goal is to push you toward your first $100,000 in bug bounties.

Ready to Start Your Bug Bounty Journey?

Before we dive into these advanced vulnerabilities, I want to help those who are just beginning their bug bounty journey. I've created a comprehensive bug bounty course that takes you from the basics all the way through to the advanced techniques we'll discuss in this article. The course includes over 100 hands-on labs covering every vulnerability type, allowing you to practice in a safe, controlled environment. Whether you're just starting out or looking to level up your skills, this structured learning path will help you build a solid foundation for your bug bounty career. Learn more about the course here →

Cross-Site Scripting (XSS)

Despite being one of the oldest web vulnerabilities, XSS continues to be a reliable source of bounties, accounting for approximately 18% of my valid submissions in the previous year. However, success in finding XSS vulnerabilities requires moving beyond basic payload testing.

Advanced XSS Methodology

Don’t just throw polyglot payloads at every input—try this instead:

  1. Start with simple HTML tags (like <u>test123nhamasec). This method allows you to:

  • Use a unique string that can be easily tracked using Chrome Developer Tools.

  • Monitor input reflection within the page to see how different HTML tags handle your text.

  • Identify potential vulnerable areas without triggering WAFs or filters.

  • Determine if any filters or sanitization mechanisms are in place to prevent XSS.

2. Investigate cross-domain implications – your input might appear in unexpected places. Pay special attention to user profile data that could propagate across different systems. Just because a field isn’t vulnerable on a specific page or application doesn’t mean it won’t be exploitable elsewhere.Next you need to Investigate cross-domain implications - your input might appear in unexpected places. Pay special attention to user profile data that could propagate across systems. Just because one field isn’t vulnerable on a specific page or application, doesn’t mean that it will not be vulnerable somewhere else.

Blind XSS deserves particular attention, as it represented one-third of successful XSS submissions. Consider implementing a combined approach: use a standard `alert(1)` for immediate confirmation while simultaneously importing a blind XSS payload for comprehensive tracking.

Server-Side Request Forgery (SSRF)

SSRF is a gold mine. 25% of my total bug bounty earnings last year came from SSRF alone—but I’m not talking about basic localhost or metadata tricks. Here’s what most hackers get wrong about SSRF. My approach to SSRF is different:

  • Analyze the application's intended functionality for URL handling. Look for features that process URLs, such as webhooks, file uploads, or dynamic imports. Understand how URLs are parsed, validated, and processed.

  • Review URL validation patterns and potential bypasses. Examine the regex for URL validation and look for edge cases that can be exploited. Test for bypasses by encoding, obfuscating, or modifying URLs.

  • Investigate trusted resource lists that might be exploitable. Check for any public lists of trusted resources (CSP headers, javascript files, CDNs, third party sites) that can be leveraged for SSRF. Identify external services that are accessible from the application.

  • Search for open redirects that could aid in SSRF exploitation. Open redirects can lead to unexpected behavior and allow for SSRF. Look for redirects that can be manipulated to access internal resources.

Make sure you recreate and test the application backend locally or on a staging environment with the same configuration as the target by looking into the user agent. Use the same browser version or any custom libraries that the target application might be using lowers your chances of missing a potential vulnerability. By replicating instances internally, you can gain a deeper understanding of the backend's behavior and identify any potential issues or syntax errors that could affect the exploitation process. This approach helps ensure that the exploit is effective and avoids any issues that could arise due to differences in environment configurations.

Look beyond traditional SSRF entry points like webhooks and import functions. For example start testing for social media links, inserting links in PDFs, or any other areas the application allows you to enter a remote link.

And one critical tip: Stop using Burp Collaborator or Interact for SSRF testing. Companies are blocking these services. If you’re serious about SSRF in 2025, set up your own interact.sh server. That’s the difference between landing an SSRF bounty and missing out.

Path Traversal

Path traversal vulnerabilities remain significant, especially when combining client-side and server-side attack vectors. Success in this area requires:

  • Understanding browser path handling mechanisms

  • Mastering URL encoding techniques

  • Identifying secondary context APIs and web proxies

  • Analyzing how different web servers process path components

Path traversal is making a serious comeback. Take the recent Splunk CVE—hackers were able to grab configuration files using basic path traversal tricks.

But here’s the problem: Most hackers just try ../../../ a few times and give up. If you really want to land high-paying path traversal bugs, you need to:

  1. Master the different URL encoding tricks.

  2. Understand how the application process paths.

  3. Know how different servers handle path components.

  4. Make it a habit to test for path traversals within any API calls

If this sounds new to you, go watch my 403 Forbidden Bypass video where I break down URL encoding tricks that most hackers miss.

Web Cache Deception: A Growing Threat

Web cache deception is becoming a bigger problem as web apps rely on more complex caching setups and CDNs. The core of this attack is tricking the cache into storing and serving sensitive content that should never be cached in the first place. Misconfigurations in how caching layers interpret requests create opportunities for exploitation.

  1. Look for Endpoints with Sensitive Data
    Start by identifying URLs that return user-specific or sensitive content. Focus on API responses, authentication-related endpoints, and pages that display personal information. If an attacker can trick the cache into storing these responses, they might later retrieve them as a public resource.

  2. Test Different File Extensions
    Many caching systems treat static file extensions (.css, .js, .png) differently from dynamic ones. Try appending these extensions to URLs that normally serve private data. If the server processes the request but the cache sees it as static, the response might get stored incorrectly.

  3. Check HTTP Headers for Caching Behavior
    Inspect responses for headers like X-Cache, Age, and Cache-Control. A response with X-Cache: HIT means the cache is serving it instead of the origin server. If you see cache hits on sensitive endpoints, there could be a misconfiguration. Tools like CAIDO’'s HTTPQL can help track cache behavior across different requests.

Modern caching layers, especially those using multiple CDNs, add complexity that can lead to subtle yet serious security issues. Understanding how these systems process requests—and where they might get confused—is key to spotting and exploiting cache deception vulnerabilities.

Supply Chain Attacks: Following the Dependencies

Supply chain attacks are where the fun is. If you’ve been paying attention, you’ve probably seen research from Alex Birsan, Lupin (Roni), and other top hackers—these guys have been hacking Apple, Microsoft, PayPal, and more using supply chain exploits.

What makes these bugs so dangerous is that they attack trust relationships—third-party scripts, package managers, CI/CD pipelines—you name it. Here’s what I focus on when hunting for these vulnerabilities:

  1. Resource Availability: How does the application handle missing resources? Does it fail gracefully, or does it leak information that an attacker can use?

  2. Dependency Management: How are dependencies managed and validated? Can you introduce a malicious dependency with the same name as a legitimate one?

  3. Build Pipeline: The build pipeline is the heart of software development. If an attacker can compromise this pipeline, they can inject malicious code into every build.

If you’re not looking at supply chain attacks in 2025, you’re leaving serious money on the table.

Race Conditions: Timing is Everything

Race conditions are security vulnerabilities that occur when multiple processes or threads access shared resources simultaneously without proper synchronization. This can lead to unintended behavior, especially in applications with high concurrency.

Common Race Condition Scenarios:

  • Multiple Gift Card Redemptions: An attacker might exploit a race condition to redeem a single-use gift card multiple times before the system updates its status.

  • Currency Transactions: By initiating multiple simultaneous transactions, an attacker could manipulate account balances, leading to unauthorized fund transfers.

  • Limited Item Purchases: In scenarios where items are in limited supply, an attacker could purchase more than the allowed quantity by sending concurrent requests.

  • Subscription and Trial Activations: An attacker might repeatedly activate trial periods or subscriptions by exploiting race conditions in the activation process.

The severity of race conditions can be amplified when combined with other vulnerabilities, such as Insecure Direct Object References (IDOR) or flaws in business logic.

Conclusion

You made it this far? That means you’re serious about bug bounties. 2025 is the year to step up your game. Focus on high-value vulnerabilities. Keep learning, testing, and hacking.

If this breakdown helped you, subscribe, join the Discord, and let’s get you to $100,000 in bug bounties this year. See you in the next one—peace. ✌️

*This article is based on real-world bug bounty hunting experience and current security trends. Always ensure you have proper authorization before testing for vulnerabilities on any system.*

Ben Sadeghipour
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Breaking Free from Duplicate Submissions: A Strategic Approach to Bug Bounty Success