Outcomes
- Identify abuse patterns across web and API surfaces
- Reason about when challenge systems genuinely improve security
Prerequisites
- Sections 1-6 completed
- Working knowledge of REST, GraphQL, and authentication flows
Section Breakdown
Lecture 38
CAPTCHA Overview
Frame the role of CAPTCHA systems inside layered detection and the tradeoffs they impose on real users.
Lecture 39
CAPTCHA Bypass Simulation
Model how challenge bypass works in practice so defensive claims can be evaluated realistically.
Lecture 40
API Abuse & Rate Limiting
Move from browser flows into abuse patterns on machine-readable APIs and rate control mechanisms.
Lecture 41
Device Fingerprint & Session Binding — Preventing Token Replay
Study how to bind sessions more tightly without creating excessive brittleness or lockouts.
Lecture 42
REST & GraphQL & WebSocket Abuse Patterns
Compare how abuse looks across query-rich and event-driven interfaces that expose different attack surfaces.
Lecture 43
Account Takeover & Credential Stuffing
Tie identity abuse, proxying, and credential reuse into a coherent defensive workflow.
Lecture 44
Fake Account & Social Bot Detection
Look at account creation abuse and lightweight signals that help triage automated social behavior.
Assignment
API & CAPTCHA Testing
Assess a sample flow for rate limiting, challenge placement, replay resistance, and abuse observability.