Security Writeups

A collection of real-world application security research, vulnerability disclosures, and technical writeups.

📖 Web Version: https://hangga.web.id/security-writeups/

Writeups

• The MFA Bypass That Wasn't an MFA Problem
  Authentication / Authorization
  https://cybersecuritywriteups.com/the-mfa-bypass-that-wasnt-an-mfa-problem-a-lesson-in-broken-api-authorization-b6f0fbd4154f

• How I Found an Email Verification Bypass on an AI Freelance Platform
  Authentication
  https://infosecwriteups.com/how-i-found-an-email-verification-bypass-on-an-ai-freelance-platform-6ad76663b658

• From Quantity Manipulation to Negative Shipping Costs
  Business Logic
  https://cybersecuritywriteups.com/from-quantity-manipulation-to-negative-shipping-costs-a-business-logic-flaw-in-an-e-commerce-73f6c80b9b17

• I Was Removed From the Organization, But My Access Still Worked
  Broken Access Control
  https://cybersecuritywriteups.com/i-was-removed-from-the-organization-but-my-access-still-worked-lessons-from-a-broken-access-151158d95f7d

• From a Simple Profile Endpoint to a 100k+ User IDOR on HackerRank
  IDOR / BOLA
  https://cybersecuritywriteups.com/from-a-simple-profile-endpoint-to-a-100k-user-idor-on-hackerrank-6f9b6e6fe746

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Application Security Engineer & Security Researcher

• Portfolio: https://hangga.web.id
• Medium: https://hangga-aji-sayekti.medium.com
• LinkedIn: https://www.linkedin.com/in/hanggaajisayekti/