Kubean is a cluster lifecycle management toolchain based on kubespray and other cluster LCM engine. The ClusterRole has * verbs of * resources. If a malicious user can access the worker node which has kubeans deployment, he/she can abuse these excessive permissions to do whatever he/she likes to the whole cluster, resulting in a cluster-level privilege escalation. This issue has been addressed in release version 0.18.0. Users are advised to upgrade. There are no known workarounds for this vulnerability.
Weakness
The product specifies permissions for a security-critical resource in a way that allows that resource to be read or modified by unintended actors.
Potential Mitigations
- Run the code in a “jail” or similar sandbox environment that enforces strict boundaries between the process and the operating system. This may effectively restrict which files can be accessed in a particular directory or which commands can be executed by the software.
- OS-level examples include the Unix chroot jail, AppArmor, and SELinux. In general, managed code may provide some protection. For example, java.io.FilePermission in the Java SecurityManager allows the software to specify restrictions on file operations.
- This may not be a feasible solution, and it only limits the impact to the operating system; the rest of the application may still be subject to compromise.
- Be careful to avoid CWE-243 and other weaknesses related to jails.
References