protect-a-form-from-abuse

name	protect-a-form-from-abuse
category	web
description	Protect a public form with layered, accessible controls and measured false-positive handling. Use when spam or automation threatens submissions without justifying a hostile experience for everyone.

protect-a-form-from-abuse

Raise the cost of abusive submissions while keeping legitimate completion safe and observable.

Procedure

1. Measure submission volume, abuse patterns, user harm, and current false positives.
2. Validate every field and enforce size, frequency, and attachment limits on the server.
3. Add low-friction signals such as timing, duplicate detection, and a hidden honeypot.
4. Rate-limit by several bounded signals without treating an IP address as a person.
5. Apply an accessible challenge only when accumulated risk justifies it.
6. Queue or moderate uncertain submissions instead of silently discarding them.
7. Give legitimate users a clear retry and support path that does not reveal detection rules.
8. Monitor block, challenge, completion, appeal, and false-positive rates by cohort.
9. Rehearse provider failure and define whether the form fails open, closed, or into review.

Guardrails

• Do not collect device or behavioral data that is unnecessary for the stated risk.
• Never rely on a client-side control without server-side enforcement.
• Avoid puzzles or interaction patterns that exclude assistive technology users.

Done

• The layered control plan and data-use rationale are documented
• Legitimate, abusive, inaccessible, and provider-failure cases are tested
• Block and false-positive metrics are recorded with a verified recovery path