CVE-2021-20182: High severity red hat openshift container platform vulnerability

Published Jan 12, 2021
·
Updated

A privilege escalation flaw was found in openshift4/ose-docker-builder. The build container runs with high privileges using a chrooted environment instead of runc. If an attacker can gain access to this build container, they can potentially utilize the raw devices of the underlying node, such as the network and storage devices, to at least escalate their privileges to that of the cluster admin. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

Other sources

A privilege escalation vulnerability exists in the build functionality of OpenShift Container Platform. An attacker with 'admin' role in a project is able to escalate privileges to cluster-admin cluster role if builds are enabled.

Red Hat

Affected Software

4 affected componentsFixes available
redhat/github.com/openshift/builder v0.0.0-20210118193943<6
6
redhat OpenShift Container Platform>=4.4<4.4.33
redhat OpenShift Container Platform>=4.5<4.5.30
redhat OpenShift Container Platform>=4.6<4.6.15

Remediation

Information

The affected build strategies include docker, source and custom builds, hence these can be disabled as per the documentation[1]. This does however, exclude the Jenkins build strategy as it is not affected and does not have to be disabled. [1] https://docs.openshift.com/container-platform/4.6/builds/securing-builds-by-strategy.html On clusters where builds are allowed only grant permissions to perform builds to users who you wish to be to able to view, modify and edit all cluster resources.

Event History

Feb 2, 2021
CVE Published
12:00 AM
Data Sourced
12:00 AM
RemedyDescriptionSeverityWeaknessAffected Software
Feb 23, 2021
CVE Published
via MITRE·09:32 PM
Data Sourced
via MITRE·09:32 PM
DescriptionWeakness

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

What is CVE-2021-20182?

CVE-2021-20182 is a privilege escalation vulnerability found in openshift4/ose-docker-builder, which allows an attacker to gain access to the build container and utilize the raw devices of the underlying node.

2

How does CVE-2021-20182 affect the software?

CVE-2021-20182 affects the openshift4/ose-docker-builder package version up to exclusive 6, running with high privileges in a chrooted environment instead of runc.

3

What is the severity of CVE-2021-20182?

CVE-2021-20182 has a severity rating of 8.8 (high).

4

How can I fix CVE-2021-20182?

To fix CVE-2021-20182, update the openshift4/ose-docker-builder package to version 6 or later.

5

Where can I find more information about CVE-2021-20182?

More information about CVE-2021-20182 can be found at the following references: - [CVE-2021-20182 - CVE Detail](https://www.cve.org/CVERecord?id=CVE-2021-20182) - [CVE-2021-20182 - NVD](https://nvd.nist.gov/vuln/detail/CVE-2021-20182) - [Bugzilla - Red Hat](https://bugzilla.redhat.com/show_bug.cgi?id=1915110) - [Red Hat Security Advisory - RHSA-2021:0281](https://access.redhat.com/errata/RHSA-2021:0281)

Contact

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