OSDOCS-20902: Add 4.21.26 z-stream release notes

[bjahagir-OpenShift]

Summary

• Adds z-stream release notes for OpenShift 4.21.26
• Jira: https://redhat.atlassian.net/browse/OSDOCS-20902
• Shipment MR: https://gitlab.cee.redhat.com/hybrid-platforms/art/ocp-shipment-data/-/merge_requests/670
• ART Dashboard: https://art-dash.engineering.redhat.com/dashboard/release/openshift-4.21
• Errata: RHSA-2026:44267 / RHBA-2026:44260 (IDs from shipment YAML; not yet live on access.redhat.com; Issued date from ship date 2026-Jul-28)

Documented

• OCPBUGS-99163 (Bug Fix / Fixed issues)

Skipped (not documented)

Key	Reason
OCPBUGS-81978	CVE-only
OCPBUGS-82922	CVE-only
OCPBUGS-84287	CVE-only
OCPBUGS-86458	CVE-only
OCPBUGS-87815	Release Note Not Required
OCPBUGS-88224	CVE-only
OCPBUGS-89700	CVE-only
OCPBUGS-90084	Internal
OCPBUGS-90523	Release Note Not Required
OCPBUGS-91632	CVE-only
OCPBUGS-92194	Internal
OCPBUGS-93806	Release Note Not Required
OCPBUGS-94077	Release Note Not Required
OCPBUGS-94092	Incomplete Bug Fix RN
OCPBUGS-94189	Incomplete Bug Fix RN
OCPBUGS-98045	Internal
OCPBUGS-98269	CVE-only
OCPBUGS-98398	Incomplete Bug Fix RN
OCPBUGS-98435	CVE-only
OCPBUGS-98628	Release Note Not Required
OCPBUGS-98747	Release Note Not Required
OCPBUGS-98966	Incomplete Bug Fix RN
OCPBUGS-99165	Release Note Not Required
OCPBUGS-99283	Internal

Scope notes

• Shipment YAML keys: 25
• Errata Fixes keys: n/a (errata not published yet)
• Draft PR until advisory pages are live; verify Issued date and synopsis against access.redhat.com when published

Test plan

• Title and issued date match access.redhat.com
• Primary + RPM advisory links correct
• Vale clean on touched files

[openshift-ci-robot]

@bjahagir-OpenShift: This pull request references OSDOCS-20902 which is a valid jira issue.

Details

In response to this:

Summary

• Adds z-stream release notes for OpenShift 4.21.26
• Jira: https://redhat.atlassian.net/browse/OSDOCS-20902
• Shipment MR: https://gitlab.cee.redhat.com/hybrid-platforms/art/ocp-shipment-data/-/merge_requests/670
• ART Dashboard: https://art-dash.engineering.redhat.com/dashboard/release/openshift-4.21
• Errata: RHSA-2026:44267 / RHBA-2026:44260 (IDs from shipment YAML; not yet live on access.redhat.com; Issued date from ship date 2026-Jul-28)

Documented

• OCPBUGS-99163 (Bug Fix / Fixed issues)

Skipped (not documented)

Key	Reason
OCPBUGS-81978	CVE-only
OCPBUGS-82922	CVE-only
OCPBUGS-84287	CVE-only
OCPBUGS-86458	CVE-only
OCPBUGS-87815	Release Note Not Required
OCPBUGS-88224	CVE-only
OCPBUGS-89700	CVE-only
OCPBUGS-90084	Internal
OCPBUGS-90523	Release Note Not Required
OCPBUGS-91632	CVE-only
OCPBUGS-92194	Internal
OCPBUGS-93806	Release Note Not Required
OCPBUGS-94077	Release Note Not Required
OCPBUGS-94092	Incomplete Bug Fix RN
OCPBUGS-94189	Incomplete Bug Fix RN
OCPBUGS-98045	Internal
OCPBUGS-98269	CVE-only
OCPBUGS-98398	Incomplete Bug Fix RN
OCPBUGS-98435	CVE-only
OCPBUGS-98628	Release Note Not Required
OCPBUGS-98747	Release Note Not Required
OCPBUGS-98966	Incomplete Bug Fix RN
OCPBUGS-99165	Release Note Not Required
OCPBUGS-99283	Internal

Scope notes

• Shipment YAML keys: 25
• Errata Fixes keys: n/a (errata not published yet)
• Draft PR until advisory pages are live; verify Issued date and synopsis against access.redhat.com when published

Test plan

• Title and issued date match access.redhat.com
• Primary + RPM advisory links correct
• Vale clean on touched files

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the openshift-eng/jira-lifecycle-plugin repository.

[openshift-ci]

Skipping CI for Draft Pull Request.
If you want CI signal for your change, please convert it to an actual PR.
You can still manually trigger a test run with /test all

[ocpdocs-previewbot]

🤖 Mon Jul 27 17:50:31 - Prow CI generated the docs preview:

https://116604--ocpdocs-pr.netlify.app/openshift-enterprise/latest/release_notes/ocp-4-21-release-notes.html

[ocpdocs-vale-bot]

🤖 [error] OpenShiftAsciiDoc.NoXrefInModules: Do not include xrefs in modules, only assemblies (exception: release notes modules).

[openshift-ci]

@bjahagir-OpenShift: all tests passed!

Full PR test history. Your PR dashboard.

Details

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