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<title>GnuTLS 3.5.4: Advanced certificate verification</title>
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<link href="Verifying-a-certificate-using-trust-on-first-use-authentication.html#Verifying-a-certificate-using-trust-on-first-use-authentication" rel="next" title="Verifying a certificate using trust on first use authentication">
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<a name="Advanced-certificate-verification"></a>
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<p>
Next: <a href="Digital-signatures.html#Digital-signatures" accesskey="n" rel="next">Digital signatures</a>, Previous: <a href="OpenPGP-certificates.html#OpenPGP-certificates" accesskey="p" rel="prev">OpenPGP certificates</a>, Up: <a href="Certificate-authentication.html#Certificate-authentication" accesskey="u" rel="up">Certificate authentication</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Function-and-Data-Index.html#Function-and-Data-Index" title="Index" rel="index">Index</a>]</p>
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<hr>
<a name="Advanced-certificate-verification-1"></a>
<h4 class="subsection">4.1.3 Advanced certificate verification</h4>
<a name="index-Certificate-verification"></a>
<p>The verification of X.509 certificates in the HTTPS and other Internet protocols is typically
done by loading a trusted list of commercial Certificate Authorities
(see <a href="Core-TLS-API.html#gnutls_005fcertificate_005fset_005fx509_005fsystem_005ftrust">gnutls_certificate_set_x509_system_trust</a>), and using them as trusted anchors.
However, there are several examples (eg. the Diginotar incident) where one of these
authorities was compromised. This risk can be mitigated by using in addition to CA certificate verification,
other verification methods. In this section we list the available in GnuTLS methods.
</p>
<table class="menu" border="0" cellspacing="0">
<tr><td align="left" valign="top">• <a href="Verifying-a-certificate-using-trust-on-first-use-authentication.html#Verifying-a-certificate-using-trust-on-first-use-authentication" accesskey="1">Verifying a certificate using trust on first use authentication</a>:</td><td> </td><td align="left" valign="top">
</td></tr>
<tr><td align="left" valign="top">• <a href="Verifying-a-certificate-using-DANE.html#Verifying-a-certificate-using-DANE" accesskey="2">Verifying a certificate using DANE</a>:</td><td> </td><td align="left" valign="top">
</td></tr>
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