A security issue was discovered in kube-apiserver that could allow node updates to bypass a Validating Admission Webhook. Clusters are only affected by this vulnerability if they run a Validating Admission Webhook for Nodes that denies admission based at least partially on the old state of the Node object. Validating Admission Webhook does not observe some previous fields.

The remote Red Hat Enterprise Linux CoreOS 4 host has packages installed that are affected by multiple vulnerabilities as referenced in the RHSA-2021:2437 advisory.

  - golang: crypto/elliptic: incorrect operations on the P-224 curve (CVE-2021-3114)

  - gogo/protobuf: plugin/unmarshal/unmarshal.go lacks certain index validation (CVE-2021-3121)

  - openshift: Injected service-ca.crt incorrectly contains additional internal CAs (CVE-2021-3636)

  - python-eventlet: improper handling of highly compressed data and memory allocation with excessive size     allows DoS (CVE-2021-21419)

  - jenkins-2-plugins/matrix-auth: Incorrect permission checks in Matrix Authorization Strategy Plugin     (CVE-2021-21623)

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

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - A security issue was discovered in kube-apiserver that could allow node updates to bypass a Validating     Admission Webhook. Clusters are only affected by this vulnerability if they run a Validating Admission     Webhook for Nodes that denies admission based at least partially on the old state of the Node object.
    Validating Admission Webhook does not observe some previous fields. (CVE-2021-25735)

Note that Nessus relies on the presence of the package as reported by the vendor.

There are packages installed that are affected by a vulnerability referenced in the following CVE:

  - A security issue was discovered in kube-apiserver that could allow node updates to bypass a Validating
    Admission Webhook. Clusters are only affected by this vulnerability if they run a Validating Admission
    Webhook for Nodes that denies admission based at least partially on the old state of the Node object.
    Validating Admission Webhook does not observe some previous fields. (CVE-2021-25735)

The remote Redhat Enterprise Linux 7 / 8 host has packages installed that are affected by multiple vulnerabilities as referenced in the RHSA-2021:2437 advisory.

    Red Hat OpenShift Container Platform is Red Hat's cloud computing Kubernetes application platform solution     designed for on-premise or private cloud deployments.

    This advisory contains the RPM packages for Red Hat OpenShift Container Platform 4.8.2. See the following     advisory for the container images for this release:

    https://access.redhat.com/errata/RHSA-2021:2438

    Security Fix(es):

    * gogo/protobuf: plugin/unmarshal/unmarshal.go lacks certain index validation (CVE-2021-3121)

    * golang: crypto/elliptic: incorrect operations on the P-224 curve (CVE-2021-3114)

    * openshift: Injected service-ca.crt incorrectly contains additional internal CAs (CVE-2021-3636)

    * python-eventlet: improper handling of highly compressed data and memory allocation with excessive size     allows DoS (CVE-2021-21419)

    * jenkins-2-plugins/matrix-auth: Incorrect permission checks in Matrix Authorization Strategy Plugin     (CVE-2021-21623)

    * jenkins-2-plugins/credentials: Reflected XSS vulnerability in Credentials Plugin (CVE-2021-21648)

    * kubernetes: Validating Admission Webhook does not observe some previous fields (CVE-2021-25735)

    * jenkins: lack of type validation in agent related REST API (CVE-2021-21639)

    * jenkins: view name validation bypass (CVE-2021-21640)

    * kubernetes: Holes in EndpointSlice Validation Enable Host Network Hijack (CVE-2021-25737)

    For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and     other related information, refer to the CVE page(s) listed in the References section.

    All OpenShift Container Platform 4.8 users are advised to upgrade to these updated packages and images     when they are available in the appropriate release channel. To check for available updates, use the     OpenShift Console or the CLI oc command. Instructions for upgrading a cluster are available at     https://docs.openshift.com/container-platform/4.8/updating/updating-cluster-between-     minor.html#understanding-upgrade-channels_updating-cluster-between-minor

Tenable has extracted the preceding description block directly from the Red Hat Enterprise Linux security advisory.

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

ID	Name	Product	Family	Severity
312421	RHCOS 4 : OpenShift Container Platform 4.8.2 (RHSA-2021:2437)	Nessus	Red Hat Local Security Checks	medium
259755	Linux Distros Unpatched Vulnerability : CVE-2021-25735	Nessus	Misc.	medium
414835	SCA: security update for k8s.io/kubernetes (GHSA-g42g-737j-qx6j)	Tenable Cloud Security	SCA Checks	medium
414835	SCA: security update for k8s.io/kubernetes (GHSA-g42g-737j-qx6j)	Tenable Self-Hosted Container Security	SCA Checks	medium
405064	Alpine: multiple k3s packages: security update to 1.20.6.1-r0	Tenable Cloud Security	Alpine Linux Local Security Checks	medium
405064	Alpine: multiple k3s packages: security update to 1.20.6.1-r0	Tenable Self-Hosted Container Security	Alpine Linux Local Security Checks	medium
400238	Alpine: multiple k3s packages: security update to 1.20.6-r0 (deprecated)	Tenable Cloud Security	Alpine Linux Local Security Checks	medium
400238	Alpine: multiple k3s packages: security update to 1.20.6-r0 (deprecated)	Tenable Self-Hosted Container Security	Alpine Linux Local Security Checks	medium
152103	RHEL 7 / 8 : OpenShift Container Platform 4.8.2 (RHSA-2021:2437)	Nessus	Red Hat Local Security Checks	high

Detections

Analytics

CVE-2021-25735

medium

Tenable Plugins

medium

medium

medium

medium

medium

medium

medium

medium

high