CVE-2021-20238

Description

It was found in OpenShift Container Platform 4 that ignition config, served by the Machine Config Server, can be accessed externally from clusters without authentication. The MCS endpoint (port 22623) provides ignition configuration used for bootstrapping Nodes and can include some sensitive data, e.g. registry pull secrets. There are two scenarios where this data can be accessed. The first is on Baremetal, OpenStack, Ovirt, Vsphere and KubeVirt deployments which do not have a separate internal API endpoint and allow access from outside the cluster to port 22623 from the standard OpenShift API Virtual IP address. The second is on cloud deployments when using unsupported network plugins, which do not create iptables rules that prevent to port 22623. In this scenario, the ignition config is exposed to all pods within the cluster and cannot be accessed externally.

Categories

3.7
CVSS
Severity: Low
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.14%
Vendor Advisory redhat.com
Affected: n/a openshift/machine-config-operator
Published at:
Updated at:

References

Link Tags
https://bugzilla.redhat.com/show_bug.cgi?id=1926568 vendor advisory mitigation issue tracking

Frequently Asked Questions

What is the severity of CVE-2021-20238?
CVE-2021-20238 has been scored as a low severity vulnerability.
How to fix CVE-2021-20238?
To fix CVE-2021-20238, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-20238 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-20238 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-20238?
CVE-2021-20238 affects n/a openshift/machine-config-operator.
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