A contact-form incident occurs when valid messages are lost, duplicated, delayed, exposed to the wrong audience, or accepted through unsafe validation. Responding well means preserving evidence while limiting further impact. Do not replace the form or clear logs before recording the affected version, time window, and destination.
Open a bounded incident record
Assign an incident identifier, owner, severity, first-observed time, form URL, frontend and handler versions, destination system, and affected period. Record who reported the issue and the exact symptom. Separate confirmed facts from hypotheses such as “the spam filter deleted it.”
Preserve deployment records, configuration changes, provider status, validation errors, delivery or queue identifiers, rate-limit events, and representative synthetic tests. Do not copy customer message bodies into an unrestricted ticket. Reference protected records and redact personal information from diagnostic attachments.
Keep events linkable
The OWASP Logging Cheat Sheet describes using an interaction identifier to link events from one user interaction and recommends a consistent classification approach for events. For a form, use a non-secret submission or trace identifier that connects the request, validation result, handler, queue, and delivery outcome without exposing the message.
Log enough to answer when the request arrived, which version handled it, whether validation passed, where it was routed, and whether downstream delivery succeeded. Avoid logging passwords, tokens, full payment data, or unnecessary form contents. Protect logs against unauthorized access and tampering.
Contain the problem
If messages are being exposed or misrouted, disable the affected route or switch to an approved safe fallback and escalate the privacy or security response. If messages are being dropped, show a truthful temporary notice and an alternate contact method whose ownership is verified. Do not display a success confirmation when the handler cannot confirm acceptance.
Pause risky deployments and preserve the current state. Restore the last known-good frontend and handler together when the rollback is compatible with current secrets, domains, and destinations. Keep anti-abuse and rate-limit controls active.
Verify validation and delivery
The OWASP Input Validation Cheat Sheet recommends early validation with syntactic and semantic checks. Run synthetic cases for valid input, missing required fields, invalid formats, maximum lengths, special characters, repeated submissions, and bot-like traffic. Confirm server-side rejection even if client checks are bypassed.
Verify the complete path: browser response, server acceptance, queue or provider receipt, downstream mailbox or ticket, timestamp, unique identifier, and monitoring event. Check refresh and retry behavior for duplicates. Test accessibility of errors and confirmation messages.
Recover and communicate
Identify messages that can be safely replayed and messages whose delivery status is uncertain. Avoid resending blindly; a duplicate can be harmful. Notify affected internal owners and users with confirmed information, the affected time range, a safe next action, and the next update time. Never claim recovery until synthetic delivery and monitoring both pass.
Close with a timeline, impact, confirmed cause, evidence references, containment, recovery validation, communications, and follow-up owners. Add a test or alert for the failure mode. Retain only the diagnostic data required by policy and remove synthetic messages through the normal retention process.
Sources
- Logging Cheat Sheet — OWASP Foundation
- Input Validation Cheat Sheet — OWASP Foundation