SB2019082915 - Multiple vulnerabilities in Kubernetes Kubernetes
Published: August 29, 2019 Updated: July 17, 2020
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 3 secuirty vulnerabilities.
1) Permissions, Privileges, and Access Controls (CVE-ID: CVE-2019-11246)
The vulnerability allows a remote non-authenticated attacker to manipulate data.
The kubectl cp command allows copying files between containers and the user machine. To copy files from a container, Kubernetes runs tar inside the container to create a tar archive, copies it over the network, and kubectl unpacks it on the user’s machine. If the tar binary in the container is malicious, it could run any code and output unexpected, malicious results. An attacker could use this to write files to any path on the user’s machine when kubectl cp is called, limited only by the system permissions of the local user. Kubernetes affected versions include versions prior to 1.12.9, versions prior to 1.13.6, versions prior to 1.14.2, and versions 1.1, 1.2, 1.4, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 1.10, 1.11.
2) Permissions, Privileges, and Access Controls (CVE-ID: CVE-2019-11247)
The vulnerability allows a remote authenticated user to read and manipulate data.
The Kubernetes kube-apiserver mistakenly allows access to a cluster-scoped custom resource if the request is made as if the resource were namespaced. Authorizations for the resource accessed in this manner are enforced using roles and role bindings within the namespace, meaning that a user with access only to a resource in one namespace could create, view update or delete the cluster-scoped resource (according to their namespace role privileges). Kubernetes affected versions include versions prior to 1.13.9, versions prior to 1.14.5, versions prior to 1.15.2, and versions 1.7, 1.8, 1.9, 1.10, 1.11, 1.12.
3) Permissions, Privileges, and Access Controls (CVE-ID: CVE-2019-11249)
The vulnerability allows a remote non-authenticated attacker to manipulate data.
The kubectl cp command allows copying files between containers and the user machine. To copy files from a container, Kubernetes runs tar inside the container to create a tar archive, copies it over the network, and kubectl unpacks it on the user’s machine. If the tar binary in the container is malicious, it could run any code and output unexpected, malicious results. An attacker could use this to write files to any path on the user’s machine when kubectl cp is called, limited only by the system permissions of the local user. Kubernetes affected versions include versions prior to 1.13.9, versions prior to 1.14.5, versions prior to 1.15.2, and versions 1.1, 1.2, 1.4, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 1.10, 1.11, 1.12.
Remediation
Install update from vendor's website.
References
- https://github.com/kubernetes/kubernetes/pull/76788
- https://groups.google.com/forum/#!topic/kubernetes-security-announce/NLs2TGbfPdo
- https://security.netapp.com/advisory/ntap-20190919-0003/
- https://access.redhat.com/errata/RHBA-2019:2816
- https://access.redhat.com/errata/RHBA-2019:2824
- https://access.redhat.com/errata/RHSA-2019:2690
- https://access.redhat.com/errata/RHSA-2019:2769
- https://github.com/kubernetes/kubernetes/issues/80983
- https://groups.google.com/d/msg/kubernetes-security-announce/vUtEcSEY6SM/v2ZZxsmtFQAJ
- https://access.redhat.com/errata/RHBA-2019:2794
- https://access.redhat.com/errata/RHSA-2019:3239
- https://access.redhat.com/errata/RHSA-2019:3811
- https://github.com/kubernetes/kubernetes/issues/80984