Summary
- Business logic flaws let attackers misuse an app’s legitimate functionality.
- Unlike simple code bugs, these are design-level weaknesses that rely on creative human understanding of the application’s workflows and assumptions.
- Left unpatched, they can cost companies money, reputation, and regulatory fines.
- As surface-level bugs get patched, more hunters are focusing on logic flaws to make an impact.
- Real-world logic bugs frequently involve insufficient data validation, client-side trust, workflow bypasses, access control, and domain-specific issues.
- Testers approach logic testing like a detective, systematically testing and questioning the application’s assumptions.
- Tools like Burp Suite Pro and scripts are handy, but require human reasoning to map bugs to the intended business flow.
- This article gives broad tips, real-world examples, and a checklist for finding logic bugs in any app.
- Sources refer to further reading and interactive labs to practice these concepts.
By Gr3yG05T
Original Article