ConceptsBrowser Warnings

Browser Warnings

The security alerts a web browser shows when something is wrong with a site's connection or certificate, such as an invalid or expired certificate, or a downgrade from HTTPS. They are a frontline signal that a connection may be unsafe.

Glossary definition

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Certificate Validation

The foundation Browser Warnings builds on, worth understanding first.

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Certificate ValidationStart here

The checks a client performs before trusting a certificate: confirming a trusted authority signed it, that it matches the expected identity, that it has not expired, and that it has not been revoked. Skipping or weakening these checks is a serious flaw.

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