RHSA-2026:20569 - Security Advisory

Topic

An update for buildah is now available for Red Hat Enterprise Linux 10.0 Extended Update Support.

Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.

Description

The buildah package provides a tool for facilitating building OCI container images. Among other things, buildah enables you to: Create a working container, either from scratch or using an image as a starting point; Create an image, either from a working container or using the instructions in a Dockerfile; Build both Docker and OCI images.

Security Fix(es):

• github.com/go-jose/go-jose/v3: github.com/go-jose/go-jose/v4: Go JOSE: Denial of Service via crafted JSON Web Encryption (JWE) object (CVE-2026-34986)
• crypto/x509: golang: Go crypto/x509: Denial of Service via inefficient certificate chain validation (CVE-2026-32281)
• crypto/tls: golang: Go crypto/tls: Denial of Service via multiple TLS 1.3 key update messages (CVE-2026-32283)
• crypto/x509: crypto/tls: golang: Go: Denial of Service vulnerability in certificate chain building (CVE-2026-32280)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Solution

For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

Affected Products

• Red Hat Enterprise Linux for x86_64 - Extended Update Support 10.0 x86_64
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 10.0 s390x
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 10.0 ppc64le
• Red Hat Enterprise Linux for ARM 64 - Extended Update Support 10.0 aarch64
• Red Hat Enterprise Linux for ARM 64 - 4 years of updates 10.0 aarch64
• Red Hat Enterprise Linux for IBM z Systems - 4 years of updates 10.0 s390x
• Red Hat Enterprise Linux for Power, little endian - 4 years of support 10.0 ppc64le
• Red Hat Enterprise Linux for x86_64 - 4 years of updates 10.0 x86_64

Fixes

• BZ - 2455470 - CVE-2026-34986 github.com/go-jose/go-jose/v3: github.com/go-jose/go-jose/v4: Go JOSE: Denial of Service via crafted JSON Web Encryption (JWE) object
• BZ - 2456333 - CVE-2026-32281 crypto/x509: golang: Go crypto/x509: Denial of Service via inefficient certificate chain validation
• BZ - 2456338 - CVE-2026-32283 crypto/tls: golang: Go crypto/tls: Denial of Service via multiple TLS 1.3 key update messages
• BZ - 2456339 - CVE-2026-32280 crypto/x509: crypto/tls: golang: Go: Denial of Service vulnerability in certificate chain building

CVEs

• CVE-2026-32280
• CVE-2026-32281
• CVE-2026-32283
• CVE-2026-34986

References

• https://access.redhat.com/security/updates/classification/#important