📰 Originally published on SecurityElites — the canonical, fully-updated version of this article.
DAY 4 OF 60
BUG BOUNTY MASTERY COURSE
FREE — ALL 60 DAYS
🟢 Day 4 — OWASP Top 10 Overview
Day 60 — Pro Hunter $$$$
04
In 2023, broken access control was found in 94% of all web applications tested. Not 94% of insecure applications. 94% of all applications — including enterprise software used by Fortune 500 companies, government agencies, and banks. The OWASP Top 10 is not a list of exotic, hard-to-find vulnerabilities. It is a list of mistakes so common they exist in almost every application on the internet.
Understanding the OWASP Top 10 is not optional in bug bounty — it is the foundational curriculum. Every significant bug bounty programme in the world references these ten categories. The HackerOne Hall of Fame is built on reports that fall into these categories. The techniques you will learn from Day 5 through Day 55 of this course are the practical implementation of these ten categories.
Today is your overview. You will understand what each category means, how it gets exploited, what it pays, and which course days teach you to find it. By the end of this lesson, you will have the complete mental map of web application security — and everything that follows will slot into that map perfectly.
📌 What Is OWASP and Why Should You Trust This List?
The Open Web Application Security Project (OWASP) is a nonprofit foundation that works to improve software security. The OWASP Top 10 is compiled from data contributed by hundreds of organisations, covering over 500,000 applications tested by security professionals worldwide. It is updated every 3–4 years to reflect the current threat landscape.
The current version — OWASP Top 10 2021 — is the standard referenced by all major bug bounty programmes, the OSCP certification, NIST guidelines, PCI DSS compliance frameworks, and every serious web security curriculum. When a company’s bug bounty policy says “we welcome reports of OWASP Top 10 vulnerabilities,” they are talking about exactly what you are about to learn.
📋 The 10 Categories You’ll Learn Today
A01Broken Access Control
A02Cryptographic Failures
A03Injection
A04Insecure Design
A05Security Misconfiguration
A06Vulnerable & Outdated Components
A07Identification & Auth Failures
A08Software & Data Integrity Failures
A09Security Logging & Monitoring Failures
A10Server-Side Request Forgery (SSRF)
securityelites.com
OWASP TOP 10 — BUG BOUNTY PAYOUT MAP (2026)
Approximate payout ranges across major bug bounty programmes
A01
Broken Access Control
$300–$10K
Found in 94% of apps
A02
Cryptographic Failures
$200–$5K
Encryption & data at rest
A03
Injection
$500–$30K
SQLi, XSS, SSTI
A04
Insecure Design
$200–$8K
Business logic flaws
A05
Security Misconfiguration
$100–$5K
Config errors & defaults
A06
Outdated Components
$100–$2K
Known CVE findings
A07
Auth Failures
$500–$50K
Account takeover = 💰
A08
Integrity Failures
$300–$10K
Insecure deserialisation
A09
Logging Failures
$100–$1K
Low — but chainable
A10
SSRF
$500–$50K
Cloud = critical
🔴 High priority targets | 🟡 Medium | 🟢 Lower severity — all are valid findings
OWASP Top 10 — Bug Bounty Payout Map. Red cards are the highest-priority targets for most beginners. A07 (Auth Failures) and A10 (SSRF) have the highest ceiling — account takeover and cloud SSRF regularly pay $10,000–$50,000+ at major programmes.
A01
Broken Access Control — The #1 Most Found Vulnerability in Bug Bounty
$300–$10,000
HIGH FREQUENCY
Course Day: 8–10
What it is: Access controls are the rules that decide who can do what — which users can view which data, which accounts can perform which actions. Broken Access Control means those rules are either missing, improperly implemented, or bypassed. It is the #1 OWASP category because it is found in 94% of tested applications — and it directly enables attackers to access data and functions they should not be able to reach.
How it manifests in bug bounty: The most common form is IDOR (Insecure Direct Object Reference) — changing a user ID, order ID, or document ID in a URL or API request and receiving another user’s data. Example: the URL /api/orders/8472 returns your order. Changing it to /api/orders/8473 returns another user’s order. That is IDOR — and it pays $300–$5,000 depending on what data is exposed.
Other A01 examples:
→ Accessing admin pages without being an admin (/admin/users returns 200 for a regular user)
→ Modifying role: "user" to role: "admin" in a request body and having it accepted
→ Deleting or modifying another user’s data by changing the resource ID in a DELETE or PUT request
→ Forced browsing — visiting authenticated pages by direct URL without going through the login flow
Course coverage: Days 8–10 cover IDOR in depth — how to find object references in requests, how to enumerate IDs systematically in Burp Suite, how to demonstrate impact, and how to write the finding up for maximum bounty.
A02
Cryptographic Failures — When Encryption Is Broken, Missing, or Misused
$200–$5,000
MEDIUM FREQUENCY
Course Day: 15–16
What it is: Previously called “Sensitive Data Exposure,” this category covers failures related to cryptography — specifically when applications transmit or store sensitive data without adequate encryption, use weak or deprecated cryptographic algorithms, or have cryptographic implementations that can be attacked. Cryptographic failures expose passwords, credit card numbers, health records, and personally identifiable information.
📖 Read the complete guide on SecurityElites
This article continues with deeper technical detail, screenshots, code samples, and an interactive lab walk-through. Read the full article on SecurityElites →
This article was originally written and published by the SecurityElites team. For more cybersecurity tutorials, ethical hacking guides, and CTF walk-throughs, visit SecurityElites.
Top comments (0)