CVE-2026-42011: Gnutls: gnutls: security bypass due to incorrect name constraint handling

Published May 6, 2026
·
Updated

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 validation. This bypass could lead to the acceptance of invalid certificates, potentially enabling spoofing or man-in-the-middle attacks against affected systems.

Affected Software

2 affected componentsFixes available
GnuTLS libgnutls
debian/gnutls28<=3.7.1-5+deb11u5, <=3.7.1-5+deb11u9, <=3.7.9-2+deb12u6, <=3.8.9-3+deb13u3
3.7.9-2+deb12u73.8.9-3+deb13u43.8.13-1

Event History

May 6, 2026
Data Sourced
via Red Hat·07:07 PM
DescriptionSeverityAffected Software
May 7, 2026
CVE Published
via MITRE·01:51 PM
Data Sourced
via MITRE·01:51 PM
DescriptionSeverityWeakness
Data Sourced
via NVD·03:16 PM
DescriptionSeverityWeakness
May 20, 2026
Data Sourced
via Debian·02:42 PM
DescriptionAffected Software
Data Sourced
via Launchpad·02:42 PM
Description
May 22, 2026
Data Sourced
via Ubuntu·02:43 PM
RemedyDescriptionSeverityAffected Software
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Frequently Asked Questions

1

What is the severity of CVE-2026-42011?

CVE-2026-42011 has been classified with a medium severity rating due to security bypass vulnerabilities.

2

How do I fix CVE-2026-42011?

To mitigate CVE-2026-42011, update GnuTLS to the latest version where the flaw has been patched.

3

What kind of applications are affected by CVE-2026-42011?

CVE-2026-42011 affects applications that utilize the GnuTLS library for handling secure communication.

4

Can CVE-2026-42011 be exploited remotely?

Yes, CVE-2026-42011 can be exploited by a remote attacker due to the flaw in name constraint handling.

5

What is the impact of CVE-2026-42011 on secure communications?

CVE-2026-42011 can lead to unauthorized bypass of security checks, compromising the integrity of secure communications.

Contact

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