hunt-business-logic

Hunt business logic bugs by enumerating auth and verification boundaries, testing step-skips and replayable tokens, validating server-side enforcement, and checking payment/webhook HMAC signature validation across checkout and subscription workflows.

A trust-boundary failure occurs when state-machine edges in application workflows improperly rely on client-side state, allowing attackers to skip verification steps, replay tokens, or tamper with webhook callbacks for unauthorized access.

Test rate limit bypass by probing rate-limiting weaknesses via spoofable IP headers, checking endpoints that fail to enforce server-side limits, and verifying if attackers can exceed thresholds to abuse high-traffic consumer platforms.

Yes, this methodology applies to marketplace and gig apps by targeting exploitable state-machine edges in checkout, verification, and webhook handling to identify unauthorized access, privacy impact, and financial loss vulnerabilities.

Validate webhook HMAC signature integrity by checking if payment callbacks enforce server-side signature validation, testing for replayable tokens, and probing for misconfigurations that allow tampering with financial decisions.

Prove business logic exploitability quickly by checking what an attacker can do, what the victim loses, and whether reproduction is feasible within minutes using URL patterns, response anomalies, and JavaScript hints.