RHCOS 4 : OpenShift Container Platform 4.22.14 (RHSA-2026:66356)

medium Nessus Plugin ID 345862

Synopsis

The remote Red Hat CoreOS host is missing one or more security updates for OpenShift Container Platform 4.22.14.

Description

The remote Red Hat Enterprise Linux CoreOS 4 host has packages installed that are affected by multiple vulnerabilities as referenced in the RHSA-2026:66356 advisory.

- encoding/asn1: golang: Go encoding/asn1: Denial of Service via excessive recursion in Unmarshal (CVE-2026-33818)

- html/template: golang: Go html/template: Cross-Site Scripting via pathological input (CVE-2026-56858)

- encoding/xml: golang: Go: Denial of Service via XML decoding recursion depth issue (CVE-2026-56859)

- net/url: golang: golang net/url: Denial of Service from quadratic complexity in path resolution (CVE-2026-56860)

- crypto/tls: golang: Golang crypto/tls: Denial of Service via indefinite KeyUpdate messages (CVE-2026-56862)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

Solution

Update the RHCOS OpenShift Container Platform 4.22.14 packages based on the guidance in RHSA-2026:66356.

See Also

https://access.redhat.com/errata/RHSA-2026:66356

https://access.redhat.com/security/updates/classification/#important

https://bugzilla.redhat.com/show_bug.cgi?id=2515815

https://bugzilla.redhat.com/show_bug.cgi?id=2515820

https://bugzilla.redhat.com/show_bug.cgi?id=2515838

https://bugzilla.redhat.com/show_bug.cgi?id=2515839

https://bugzilla.redhat.com/show_bug.cgi?id=2515840

http://www.nessus.org/u?49c2233e

Plugin Details

Severity: Medium

ID: 345862

File Name: rhcos-RHSA-2026-66356.nasl

Version: 1.1

Type: Local

Agent: unix

Published: 9/15/2026

Updated: 9/15/2026

Supported Sensors: Frictionless Assessment AWS, Frictionless Assessment Azure, Frictionless Assessment Agent, Nessus Agent, Agentless Assessment, Continuous Assessment, Tenable Cloud Security, Tenable Self-Hosted Container Security, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 4.3

Percentile: 53.51

Vendor

Vendor Severity: Important

CVSS v2

Risk Factor: High

Base Score: 9.4

Temporal Score: 7

Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:N

CVSS Score Source: CVE-2026-56858

CVSS v3

Risk Factor: Medium

Base Score: 6.1

Temporal Score: 5.3

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:redhat:enterprise_linux:8:coreos, cpe:/o:redhat:enterprise_linux:9:coreos, p-cpe:/a:redhat:enterprise_linux:cri-o, p-cpe:/a:redhat:enterprise_linux:cri-tools, p-cpe:/a:redhat:enterprise_linux:openshift-hyperkube, p-cpe:/a:redhat:enterprise_linux:openshift-kube-apiserver, p-cpe:/a:redhat:enterprise_linux:openshift-kube-controller-manager, p-cpe:/a:redhat:enterprise_linux:openshift-kube-scheduler, p-cpe:/a:redhat:enterprise_linux:openshift-kubelet, p-cpe:/a:redhat:enterprise_linux:openshift

Required KB Items: Host/local_checks_enabled, Host/RedHat/release, Host/RedHat/rpm-list, Host/cpu

Exploit Ease: No known exploits are available

Patch Publication Date: 9/15/2026

Vulnerability Publication Date: 8/13/2026

Reference Information

CVE: CVE-2026-33818, CVE-2026-56858, CVE-2026-56859, CVE-2026-56860, CVE-2026-56862

CWE: 1050, 770, 776, 79

RHSA: 2026:66356