CVE-2021-20182

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.

Mitigation

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&gt;

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.