Openshift-controller-manager: elevated build pods can lead to node compromise in openshift
A flaw was found in OpenShift. This issue occurs due to the misuse of elevated privileges in the OpenShift Container Platform's build process. During the build initialization step, the git-clone container is run with a privileged security context, allowing unrestricted access to the node. An attacker with developer-level access can provide a crafted .gitconfig file containing commands executed during the cloning process, leading to arbitrary command execution on the worker node. An attacker running code in a privileged container could escalate their permissions on the node running the container.
Cluster admins can follow the instructions in "Securing Builds by Strategy" to block use of the "Docker" and “Source” build strategies on a cluster, or restrict the use to a set of highly trusted users, until the cluster is able to be upgraded.
https://docs.openshift.com/container-platform/4.16/cicd/builds/securing-builds-by-strategy.html
Exploits
Credits
This issue was discovered by Thibault Guittet (Red Hat).