RHSA-2026:67148 — Security Advisory

An update for osbuild-composer is now available for Red Hat Enterprise Linux 8.

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.

A service for building customized OS artifacts, such as VM images and OSTree commits, that uses osbuild under the hood. Besides building images for local usage, it can also upload images directly to cloud. It is compatible with composer-cli and cockpit-composer clients.

Security Fix(es):

• crypto/internal/nistec: golang: Timing sidechannel for P-256 on ppc64le in crypto/internal/nistec (CVE-2025-22866)

• crypto/x509: golang: Go crypto/x509: Denial of Service via inefficient certificate chain validation (CVE-2026-32281)

• net/mail: golang: net/mail: Denial of Service via pathological email address parsing (CVE-2026-42499)

• mime: golang: Golang MIME: Denial of Service via maliciously-crafted MIME header (CVE-2026-42504)

• github.com/open-telemetry/opentelemetry-go: go.opentelemetry.io/otel/baggage: go.opentelemetry.io/otel/propagation: OpenTelemetry-Go: Denial of Service via oversized baggage headers (CVE-2026-41178)

• github.com/labstack/echo: Echo: Unauthorized Information Disclosure via URL Path Decoding Discrepancy (CVE-2026-55677)

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.