Pepr is a type safe K8s middleware. Prior to 1.0.5 , Pepr defaults to a cluster-admin RBAC configuration and does not explicitly force or enforce least-privilege guidance for module authors. The default behavior exists to make the “getting started” experience smooth: new users can experiment with Pepr and create resources dynamically without needing to pre-configure RBAC. This vulnerability is fixed in 1.0.5.
Weakness
The elevated privilege level required to perform operations such as chroot() should be dropped immediately after the operation is performed.
Potential Mitigations
- Compartmentalize the system to have “safe” areas where trust boundaries can be unambiguously drawn. Do not allow sensitive data to go outside of the trust boundary and always be careful when interfacing with a compartment outside of the safe area.
- Ensure that appropriate compartmentalization is built into the system design, and the compartmentalization allows for and reinforces privilege separation functionality. Architects and designers should rely on the principle of least privilege to decide the appropriate time to use privileges and the time to drop privileges.
Related Attack Patterns
- https://cwe.mitre.org/data/definitions/17.html
- https://cwe.mitre.org/data/definitions/35.html
- https://cwe.mitre.org/data/definitions/76.html