CVE-2026-91769 TLS Hostname Verification Falls Back to CN After SAN Mismatch

PHP's OpenSSL stream peer verification checks the certificate's subjectAltName entries first and, whenever no entry matches, falls back to the Common Name. RFC 6125 requires the CN to be ignored once the certificate presents any service identity, so a certificate carrying a non-matching DNS SAN w...

CVE-2026-59969 Apache ZooKeeper: Improper validation of certificate with host mismatch in FIPS mode

Apache ZooKeeper quorum TLS fails to enforce peer hostname verification in FIPS-mode deployments. When sslQuorum=true, zookeeper.fips-mode=true, ssl.quorum.hostnameVerification=true, and ssl.quorum.clientHostnameVerification=true are enabled, the Java SSLSocket quorum path accepts a CA-trusted pe...

OpenSearch has ineffective TLS certificate hostname verification

Description A regression was introduced in OpenSearch 2.18.0 that caused the plugins.security.ssl.transport.enforcehostnameverification setting to be ineffective. When this setting was enabled, OpenSearch did not verify that the hostname in a connecting node's TLS certificate matched the hostname...

GHSA-X5HG-X4GV-J98M OpenSearch has ineffective TLS certificate hostname verification

Description A regression was introduced in OpenSearch 2.18.0 that caused the plugins.security.ssl.transport.enforcehostnameverification setting to be ineffective. When this setting was enabled, OpenSearch did not verify that the hostname in a connecting node's TLS certificate matched the hostname...

SUSE CVE-2020-15719

libldap in certain third-party OpenLDAP packages has a certificate-validation flaw when the third-party package is asserting RFC6125 support. It considers CN even when there is a non-matching subjectAltName SAN. This is fixed in, for example, openldap-2.4.46-10.el8 in Red Hat Enterprise Linux...