RHSA-2026:70640 — Security Advisory

An update for buildah is now available for Red Hat Enterprise Linux 9.

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.

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):

• buildah: Go net/http: Unencrypted HTTP/2 connections vulnerable to Denial of Service (CVE-2026-56853)

• buildah: Go html/template: Cross-Site Scripting via pathological input (CVE-2026-56858)

• buildah: Go encoding/asn1: Denial of Service via excessive recursion in Unmarshal (CVE-2026-33818)

• buildah: golang net/url: Denial of Service from quadratic complexity in path resolution (CVE-2026-56860)

• buildah: Golang crypto/tls: Denial of Service via indefinite KeyUpdate messages (CVE-2026-56862)

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.