RHSA-2026:57541HighCVSS 8.2

Red Hat Security Advisory: osbuild-composer security update

Published
August 20, 2026
Last Modified
August 25, 2026

🔗 CVE IDs covered (2)

CVE-2026-39821 →CVE-2026-55677 →

📋 Description

CVE-2026-39821 — golang.org/x/net/idna: golang: net/http: golang.org/x/net/idna: Privilege escalation via incorrect Punycode label processing CVE-2026-55677 — github.com/labstack/echo: Echo: Unauthorized Information Disclosure via URL Path Decoding Discrepancy

🎯 Affected products34

  • Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • osbuild-composer-0:132.2-10.el9_6.aarch64 as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • osbuild-composer-0:132.2-10.el9_6.ppc64le as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • osbuild-composer-0:132.2-10.el9_6.s390x as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • osbuild-composer-0:132.2-10.el9_6.src as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • osbuild-composer-0:132.2-10.el9_6.x86_64 as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • osbuild-composer-core-0:132.2-10.el9_6.aarch64 as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • osbuild-composer-core-0:132.2-10.el9_6.ppc64le as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • osbuild-composer-core-0:132.2-10.el9_6.s390x as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • osbuild-composer-core-0:132.2-10.el9_6.x86_64 as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • osbuild-composer-core-debuginfo-0:132.2-10.el9_6.aarch64 as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • osbuild-composer-core-debuginfo-0:132.2-10.el9_6.ppc64le as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • osbuild-composer-core-debuginfo-0:132.2-10.el9_6.s390x as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • osbuild-composer-core-debuginfo-0:132.2-10.el9_6.x86_64 as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • osbuild-composer-debuginfo-0:132.2-10.el9_6.aarch64 as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • osbuild-composer-debuginfo-0:132.2-10.el9_6.ppc64le as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • osbuild-composer-debuginfo-0:132.2-10.el9_6.s390x as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • osbuild-composer-debuginfo-0:132.2-10.el9_6.x86_64 as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • osbuild-composer-debugsource-0:132.2-10.el9_6.aarch64 as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • osbuild-composer-debugsource-0:132.2-10.el9_6.ppc64le as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • osbuild-composer-debugsource-0:132.2-10.el9_6.s390x as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • osbuild-composer-debugsource-0:132.2-10.el9_6.x86_64 as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • osbuild-composer-tests-debuginfo-0:132.2-10.el9_6.aarch64 as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • osbuild-composer-tests-debuginfo-0:132.2-10.el9_6.ppc64le as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • osbuild-composer-tests-debuginfo-0:132.2-10.el9_6.s390x as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • osbuild-composer-tests-debuginfo-0:132.2-10.el9_6.x86_64 as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • osbuild-composer-worker-0:132.2-10.el9_6.aarch64 as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • osbuild-composer-worker-0:132.2-10.el9_6.ppc64le as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • osbuild-composer-worker-0:132.2-10.el9_6.s390x as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • osbuild-composer-worker-0:132.2-10.el9_6.x86_64 as a component of Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • +4 more not shown

✅ Remediation

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 Workaround: Upgrade to a fixed golang.org/x/net release that includes the idna correction, via updated golang or dependent package rebuilds. Workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.

🔗 References (5)