mTLS
Mutual TLS, where client and server authenticate with certificates during connection establishment.
What mTLS does not show
It verifies certificate possession, not whether an application request is safe.
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 · Input validation · Output validation · Allowlist · Denylist · SSRF · RCE · Credential scope · OAuth scope · API key · Bearer token · 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 mTLS
What is mTLS?
Mutual TLS, where client and server authenticate with certificates during connection establishment.
What does mTLS not show or guarantee?
It verifies certificate possession, not whether an application request is safe.
Which area of the glossary does mTLS 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.
← Bearer token · Rate-limit policy →
See it in the full glossary · 772 terms across 19 areas.
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