Input validation
Checking supplied values against allowed types, formats, ranges, and business rules.
What Input validation does not show
Schema validation is one layer and cannot detect every harmful valid value.
Related terms in Security and privacy
Where an agent, a tool or a page can be turned against its operator, and the controls that limit the damage without proving safety.
X-Frame-Options · frame-ancestors · Referrer-Policy · Permissions-Policy · Encrypted Client Hello · lookalike domain · homoglyph · incident switch · high-risk field · Indirect prompt injection · Direct prompt injection · Jailbreak · Data exfiltration · Sensitive information disclosure · Secret leakage · Insecure output handling · Excessive agency · Least privilege · Trust boundary · Output validation · Allowlist · Denylist · SSRF · RCE · Credential scope · OAuth scope · API key · Bearer token · mTLS · Rate-limit policy · Audit log · PII · Data minimization · Purpose limitation · Retention period · Data residency · Tenant isolation · Threat model · DMARC · DMARC alignment · SPF · DKIM · MTA-STS · TLS-RPT · CAA record · DNSSEC · hard bounce
Questions about Input validation
What is Input validation?
Checking supplied values against allowed types, formats, ranges, and business rules.
What does Input validation not show or guarantee?
Schema validation is one layer and cannot detect every harmful valid value.
Which area of the glossary does Input validation belong to?
Security and privacy: Where an agent, a tool or a page can be turned against its operator, and the controls that limit the damage without proving safety.
← Trust boundary · Output validation →
See it in the full glossary · 772 terms across 19 areas.
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