CVE-2026-6731 X.509 name constraint bypass via Subject CN treated as a DNS name

X.509 name constraint bypass via the Subject Common Name when treated as a DNS-type name. A certificate whose Subject CN violates an issuing CA's DNS name constraints could be accepted...

CVE-2026-6731

CVE-2026-6731 describes an X.509 name constraint bypass where the Subject CN is treated as a DNS-type name, allowing a certificate to pass DNS constraints if the CN violates them. Public sources (NVD and related feeds) reference this bypass and provide CVSS metrics (v3.1: 7.5, Network, High impac...

EUVD-2026-39549

Certificates with wildcard DNS SANs e.g. .example.com bypassed CA name-constraint checks. A certificate with a wildcard DNS SAN that should be rejected by the issuing CA's permitted/excluded DNS name constraints could be accepted...

CVE-2026-10592

CVE-2026-10592 concerns certificates with wildcard DNS SANs (e.g., *.example.com) bypassing CA name-constraint checks. A wildcard SAN that should be rejected by the issuing CA’s permitted/excluded DNS name constraints could be accepted, enabling potential mis-issuance. The provided documents refe...

CVE-2026-10592 Wildcard DNS SAN bypasses CA name-constraint checks

Certificates with wildcard DNS SANs e.g. .example.com bypassed CA name-constraint checks. A certificate with a wildcard DNS SAN that should be rejected by the issuing CA's permitted/excluded DNS name constraints could be accepted...

CVE-2026-10592 Wildcard DNS SAN bypasses CA name-constraint checks

Certificates with wildcard DNS SANs e.g. .example.com bypassed CA name-constraint checks. A certificate with a wildcard DNS SAN that should be rejected by the issuing CA's permitted/excluded DNS name constraints could be accepted...

gnutls: GnuTLS: Policy bypass due to case-sensitive nameConstraints comparison

A flaw was found in gnutls. This vulnerability occurs because gnutls performs case-sensitive comparisons of nameConstraints labels, specifically for dNSName DNS or rfc822Name email constraints within excludedSubtrees or permittedSubtrees. A remote attacker can exploit this by crafting a leaf...

gnutls: gnutls: Security bypass due to incorrect name constraint handling

A flaw was found in gnutls. This vulnerability occurs because permitted name constraints were incorrectly ignored when previous Certificate Authorities CAs only had excluded name constraints. A remote attacker could exploit this to bypass critical name constraint checks during certificate...

Security Bulletin: Multiple Vulnerabilities in cryptography bundled with IBM Fusion, IBM Fusion HCI, IBM Fusion Data Cataloging, and IBM Fusion Content-Aware Storage

Summary IBM Fusion, IBM Fusion HCI, IBM Fusion Data Cataloging, and IBM Fusion Content-Aware Storage include the cryptography library, which is vulnerable to a critical buffer overflow and an improper certificate validation flaw. A classic buffer overflow vulnerability exists when non-contiguous...

PT-2026-52562

Name of the Vulnerable Software and Affected Versions The product name cannot be determined affected versions not specified Description Certificates containing wildcard DNS Subject Alternative Names SANs, such as .example.com, bypass name-constraint checks performed by the Certificate Authority C...

PT-2026-52589

Name of the Vulnerable Software and Affected Versions The product name cannot be determined affected versions not specified Description A flaw exists where X.509 name constraints can be bypassed when the Subject Common Name is treated as a DNS-type name. This allows a certificate to be accepted...

PT-2026-52623

Name of the Vulnerable Software and Affected Versions wolfSSL affected versions not specified Description A configuration issue occurs when WOLFSSL IP ALT NAME is not defined, leading to a bypass of iPAddress name constraints. In this state, the software fails to enforce IP address constraints se...

tomcat: Apache Tomcat: Improper Authorization Allows Security Constraint Bypass

A flaw was found in Apache Tomcat where access control rules for the default servlet are improperly handled. An attacker can exploit this issue to bypass specific HTTP method restrictions, potentially gaining unauthorized access to protected application resources...

tomcat: Apache Tomcat: Misleading security logs due to incorrect control flow

A flaw was found in Apache Tomcat. Due to an always-incorrect control flow implementation, special roles and empty authorization constraints were not accurately included when the effective web.xml configuration was logged. This could lead to a security oversight where administrators might...

gnutls security update

3.8.10-4 - Fix CVE-2026-33846 DTLS fragment reassembly, High, heap overwrite - Fix CVE-2026-42009 DTLS fragment reassembly, High, undefined behaviour - Fix CVE-2026-33845 DTLS fragment reassembly, High, heap overread - Fix CVE-2026-42010 PSK authentication, High, authentication bypass - Fix...

gnutls security fix update

3.8.10-4fips - Add FIPS package change: add fips suffix to Release and set Epoch to 10 Orabug: 35925409 - Update FIPS module name for Oracle Linux Orabug: 35925409 3.8.10-4 - Fix CVE-2026-33846 DTLS fragment reassembly, High, heap overwrite - Fix CVE-2026-42009 DTLS fragment reassembly, High,...

Fixed in Apache Tomcat 9.0.119

Moderate: Security constraints for default servlet ignored method CVE-2026-55956 If security constraints were specified for the default servlet, any method or method omission configured as part of the constraint was ignored. This was fixed with commit a0374c45. This issue was reported to the Tomc...

crypto/x509: golang: Go crypto/x509: Certificate validation bypass due to incorrect DNS constraint application

A flaw was found in the crypto/x509 package within Go golang. When verifying a certificate chain, excluded DNS Domain Name System constraints are not correctly applied to wildcard DNS Subject Alternative Names SANs if the case of the SAN differs from the constraint. This oversight could allow an...

crypto/x509: Incorrect enforcement of email constraints in crypto/x509

A certificate validation flaw has been discovered in the golang crypto/x509 module. When verifying a certificate chain which contains a certificate containing multiple email address constraints which share common local portions but different domain portions, these constraints will not be properly...

crypto/x509: Incorrect enforcement of email constraints in crypto/x509

A certificate validation flaw has been discovered in the golang crypto/x509 module. When verifying a certificate chain which contains a certificate containing multiple email address constraints which share common local portions but different domain portions, these constraints will not be properly...