RHSA-2026:66016HighCVSS 8.2

Red Hat Security Advisory: osbuild-composer security update

Published
September 9, 2026
Last Modified
September 17, 2026

🔗 CVE IDs covered (10)

CVE-2026-56853 →CVE-2026-56859 →CVE-2026-56860 →CVE-2026-56862 →CVE-2024-9355 →CVE-2026-56858 →CVE-2024-45336 →CVE-2026-33818 →CVE-2026-39820 →CVE-2026-39821 →

📋 Description

CVE-2024-9355 — golang-fips: Golang FIPS zeroed buffer CVE-2024-45336 — golang: net/http: net/http: sensitive headers incorrectly sent after cross-domain redirect CVE-2026-33818 — encoding/asn1: golang: Go encoding/asn1: Denial of Service via excessive recursion in Unmarshal CVE-2026-39820 — net/mail: golang: Go net/mail: Denial of Service via crafted email inputs CVE-2026-39821 — golang.org/x/net/idna: golang: net/http: golang.org/x/net/idna: Privilege escalation via incorrect Punycode label processing CVE-2026-56853 — net/http: golang: Go net/http: Unencrypted HTTP/2 connections vulnerable to Denial of Service CVE-2026-56858 — html/template: golang: Go html/template: Cross-Site Scripting via pathological input CVE-2026-56859 — encoding/xml: golang: Go: Denial of Service via XML decoding recursion depth issue CVE-2026-56860 — net/url: golang: golang net/url: Denial of Service from quadratic complexity in path resolution CVE-2026-56862 — crypto/tls: golang: Golang crypto/tls: Denial of Service via indefinite KeyUpdate messages

🎯 Affected products34

  • Red Hat Enterprise Linux AppStream (v. 8)
  • osbuild-composer-0:101.5-2.el8_10.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • osbuild-composer-0:101.5-2.el8_10.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • osbuild-composer-0:101.5-2.el8_10.s390x as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • osbuild-composer-0:101.5-2.el8_10.src as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • osbuild-composer-0:101.5-2.el8_10.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • osbuild-composer-core-0:101.5-2.el8_10.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • osbuild-composer-core-0:101.5-2.el8_10.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • osbuild-composer-core-0:101.5-2.el8_10.s390x as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • osbuild-composer-core-0:101.5-2.el8_10.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • osbuild-composer-core-debuginfo-0:101.5-2.el8_10.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • osbuild-composer-core-debuginfo-0:101.5-2.el8_10.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • osbuild-composer-core-debuginfo-0:101.5-2.el8_10.s390x as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • osbuild-composer-core-debuginfo-0:101.5-2.el8_10.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • osbuild-composer-debuginfo-0:101.5-2.el8_10.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • osbuild-composer-debuginfo-0:101.5-2.el8_10.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • osbuild-composer-debuginfo-0:101.5-2.el8_10.s390x as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • osbuild-composer-debuginfo-0:101.5-2.el8_10.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • osbuild-composer-debugsource-0:101.5-2.el8_10.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • osbuild-composer-debugsource-0:101.5-2.el8_10.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • osbuild-composer-debugsource-0:101.5-2.el8_10.s390x as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • osbuild-composer-debugsource-0:101.5-2.el8_10.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • osbuild-composer-tests-debuginfo-0:101.5-2.el8_10.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • osbuild-composer-tests-debuginfo-0:101.5-2.el8_10.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • osbuild-composer-tests-debuginfo-0:101.5-2.el8_10.s390x as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • osbuild-composer-tests-debuginfo-0:101.5-2.el8_10.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • osbuild-composer-worker-0:101.5-2.el8_10.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • osbuild-composer-worker-0:101.5-2.el8_10.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • osbuild-composer-worker-0:101.5-2.el8_10.s390x as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • osbuild-composer-worker-0:101.5-2.el8_10.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 8)
  • +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: 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. 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. Workaround: Upgrade to a fixed golang.org/x/net release that includes the idna correction, via updated golang or dependent package rebuilds.

🔗 References (13)