Trust boundary
The point where data or control moves between components with different assurance levels.
What Trust boundary does not show
Every crossing needs explicit validation rather than inherited trust.
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 · Input validation · 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 Trust boundary
What is Trust boundary?
The point where data or control moves between components with different assurance levels.
What does Trust boundary not show or guarantee?
Every crossing needs explicit validation rather than inherited trust.
Which area of the glossary does Trust boundary 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.
← Least privilege · Input validation →
See it in the full glossary · 772 terms across 19 areas.
Free browser extension
See this on any site you visit, in one click.
CrawlCheck for Chrome grades every site you visit A–F and shows, from your own browser, what search engines and AI assistants are actually served. Free, no account.