CVE-2021-20238
Published: 01 April 2022
Summary
CVE-2021-20238 is a low-severity Improper Authentication (CWE-287) vulnerability in Redhat Openshift Container Platform. Its CVSS base score is 3.7 (Low).
Operationally, ranked at the 47.8th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2021-7677
Vulnerability details
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…
more
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.
- CWE(s)
Related Threats
No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.
Affected Assets
Mitigating Controls
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Session content review can reveal authentication bypasses or failures in session establishment.
Assessments check authentication mechanisms for correct implementation and effectiveness, reducing successful authentication bypass attempts.
Documented IA policy and procedures require proper authentication mechanisms to be defined and followed, reducing improper authentication.
Requires adaptive authentication under specific conditions, directly strengthening authentication mechanisms against improper or insufficient authentication.
Identity providers centralize and enforce authentication mechanisms, reducing improper authentication.
Requires unique identification and authentication of organizational users, directly preventing improper authentication.
Enforces unique device identification and authentication before any connection is established, directly mitigating improper authentication weaknesses.
Directly requires implementation of compliant authentication mechanisms to cryptographic modules, preventing improper authentication.