Personal Identifiable Information (PII) leakage during session replay is not just a bug. It is a silent threat, hidden inside well-intentioned tools meant to improve user experience. When replay platforms capture raw keystrokes, form inputs, or on-screen data without strict controls, they may collect sensitive data that should never leave the browser. Once that happens, you’ve lost control over compliance, security, and user trust.
The challenge is simple to describe but hard to master: capture enough user interaction to debug and improve performance, but block anything that exposes PII. Adding filters after the fact is too late—PII might already be flowing into logs and storage systems where it persists and propagates. The only sustainable solution is prevention at the capture layer.
Effective PII leakage prevention in session replay starts with strict input masking before any data is recorded. Masking must happen client-side to guarantee that sensitive values never reach your servers. Detecting fields by name is not enough. Attackers and mistakes often come from unexpected UI changes, so masking must be dynamic and context-aware.
Redaction should cover text, attributes, and user events. Elements like payment forms, authentication flows, and profile editors need explicit handling so even hidden values are never stored. For maximum protection, combine DOM scanning for sensitive patterns with strict deny-lists and safe-listing trusted elements only.