diff --git a/modules/zstream-4-20-26.adoc b/modules/zstream-4-20-26.adoc
new file mode 100644
index 000000000000..c070fb2bc6a1
--- /dev/null
+++ b/modules/zstream-4-20-26.adoc
@@ -0,0 +1,39 @@
+// Module included in the following assemblies:
+//
+// * release_notes/ocp-4-20-release-notes.adoc
+
+:_mod-docs-content-type: REFERENCE
+[id="zstream-4-20-26_{context}"]
+= RHSA-2026:27063 - {product-title} {product-version}.26 fixed issues and security update
+
+Issued: 23 June 2026
+
+[role="_abstract"]
+{product-title} release {product-version}.26 is now available. The list of fixed issues that are included in the update is documented in the link:https://access.redhat.com/errata/RHSA-2026:27063[RHSA-2026:20763] advisory. The RPM packages that are included in the update are provided by the link:https://access.redhat.com/errata/RHBA-2026:27059[RHBA-2026:27059] advisory.
+
+Space precluded documenting all of the container images for this release in the advisory.
+
+You can view the container images in this release by running the following command:
+
+[source,terminal]
+----
+$ oc adm release info 4.20.26 --pullspecs
+----
+
+[id="zstream-4-20-26-enhancements_{context}"]
+== Enhancements
+
+* You can now set `unhealthyPodEvictionPolicy` to `AlwaysAllow` on all Pod Disruption Budgets (PDBs) for control plane pods. This means pods not yet healthy are considered disrupted and can be evicted regardless of whether the criteria in a PDB is met. (link:https://issues.redhat.com/browse/OCPBUGS-85825[OCPBUGS-85825])
+
+[id="zstream-4-20-26-fixed-issues_{context}"]
+== Fixed issues
+
+* Before this update, when a user applied a `MachineConfig` object to install extensions, the Machine Config Operator (MCO) did not validate that all packages were installed. This would lead to situations where users believed their extension installation was successful, but packages were actually missing. With this release, the MCO validates during post node reboot that all packages associated with the desired extension were successfully installed before reporting a successful update. If one of more package is not present, the node, and subsequently the associated `MachineConfigPool` degrades. (link:https://issues.redhat.com/browse/OCPBUGS-86864[OCPBUGS-86864])
+
+* Before this update, the router liveness probe used an HTTP backend check to monitor HAProxy health. As a consequence, when HAProxy reached its `maxconn` connection limit due to client traffic, the HTTP health check failed and Kubernetes unnecessarily restarted the router pods. With this update, the router liveness probe uses an HAProxy admin socket check instead of an HTTP backend check. As a result, router pods remain stable when HAProxy reaches its maxconn connection limit due to client traffic, preventing unnecessary restarts. (link:https://issues.redhat.com/browse/OCPBUGS-67161[OCPBUGS-67161])
+
+
+[id="zstream-4-20-26-updating_{context}"]
+== Updating
+
+To update an {product-title} 4.20 cluster to this latest release, see xref:../updating/updating_a_cluster/updating-cluster-cli.adoc#updating-cluster-cli[Updating a cluster using the CLI].
diff --git a/release_notes/ocp-4-20-release-notes.adoc b/release_notes/ocp-4-20-release-notes.adoc
index 22dc680481d3..9914bfe4fa2b 100644
--- a/release_notes/ocp-4-20-release-notes.adoc
+++ b/release_notes/ocp-4-20-release-notes.adoc
@@ -3021,6 +3021,9 @@ In both cases, the installation program generates a user-assigned identity. (lin
 
 include::modules/rn-async-errata.adoc[leveloffset=+1]
 
+// 4.20.26 release notes
+include::modules/zstream-4-20-26.adoc[leveloffset=+2]
+
 // 4.20.25 release notes
 include::modules/zstream-4-20-25.adoc[leveloffset=+2]