CVE-2026-42013

Publication date 30 April 2026

Last updated 20 May 2026

Ubuntu priority

Why this priority?

Description

Validation of certificates with oversized Subject Alternative Names would fall back to checking DNS hostnames against Common Name.

Status

Show unmaintained releases

Package	Ubuntu Release	Status
gnutls28	26.04 LTS resolute	Fixed 3.8.12-2ubuntu1.1
	25.10 questing	Fixed 3.8.9-3ubuntu2.2
	24.04 LTS noble	Fixed 3.8.3-1.1ubuntu3.6
	22.04 LTS jammy	Fixed 3.7.3-4ubuntu1.9
	20.04 LTS focal	Needs evaluation
	18.04 LTS bionic	Needs evaluation
	16.04 LTS xenial	Needs evaluation

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package	Patch details
gnutls28	Upstream: 29801be

References

Related Ubuntu Security Notices (USN)

USN-8284-1
GnuTLS vulnerabilities
20 May 2026

Other references

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