CA/Browser Forum

Audit Criteria

The CA / Browser Forum requires that all audits of Certification Authorities be performed by qualified auditors in accordance with an eligible audit scheme, such as the WebTrust® Program for Certification Authorities or ETSI. Also allowed, subject to confirmation by the browser to which a CA wishes to submit its root, are schemes that audit conformance to ISO 21188 or government audit schemes, where the CA is required by law or regulation (i.e. its Certificate Policy) to use a different internal audit scheme, provided that the audit either (a) encompasses all requirements of one of the above schemes or (b) consists of comparable criteria that are available for public review.

The CA / Browser Forum’s audit requirements are consistent with those of Mozilla, which states its audit policy in sections 8 through 17 of its CA Certificate Inclusion Policy found at

Below are links to the respective web pages for the CABF-recognized audit frameworks of WebTrust and ETSI:


Internal URL – /about/information/auditors-and-assessors/webtrust-for-cas/

External URL –


Internal URL – /about/information/auditors-and-assessors/etsi/

External URL –

For additional information from the CA / Browser Forum about auditing available on this website, see /about/information/auditors-and-assessors/.

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Ballot SMC06: Post implementation clarification and corrections

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The Certification Authority Browser Forum (CA/Browser Forum) is a voluntary gathering of Certificate Issuers and suppliers of Internet browser software and other applications that use certificates (Certificate Consumers).