Vulnerabilities

A security issue was discovered in ingress-nginx where a combination of Ingress annotations can be used to inject configuration into nginx. This can lead to arbitrary code execution in the context of the ingress-nginx controller, and disclosure of Secrets accessible to the controller. (Note that in the default installation, the controller can access all Secrets cluster-wide.)

A security issue was discovered in ingress-nginx where the `nginx.ingress.kubernetes.io/rewrite-target` Ingress annotation can be used to inject configuration into nginx. This can lead to arbitrary code execution in the context of the ingress-nginx controller, and disclosure of Secrets accessible to the controller. (Note that in the default installation, the controller can access all Secrets cluster-wide.)

A security issue was discovered in the Kubernetes Image Builder versions <= v0.1.37 where default credentials are enabled during the image build process. Virtual machine images built using the Proxmox provider do not disable these default credentials, and nodes using the resulting images may be accessible via these default credentials. The credentials can be used to gain root access. Kubernetes clusters are only affected if their nodes use VM images created via the Image Builder project with its Proxmox provider.

A flaw was found in cri-o. A malicious container can create a symbolic link to arbitrary files on the host via directory traversal (“../“). This flaw allows the container to read and write to arbitrary files on the host system.

A security issue was discovered in Kubernetes where a user that can create pods and persistent volumes on Windows nodes may be able to escalate to admin privileges on those nodes. Kubernetes clusters are only affected if they are using an in-tree storage plugin for Windows nodes.

A security issue was discovered in kube-apiserver that allows an aggregated API server to redirect client traffic to any URL. This could lead to the client performing unexpected actions as well as forwarding the client's API server credentials to third parties.

A security issue was discovered in Kubernetes where a user that can create pods on Windows nodes running kubernetes-csi-proxy may be able to escalate to admin privileges on those nodes. Kubernetes clusters are only affected if they include Windows nodes running kubernetes-csi-proxy.

A security issue was discovered in Kubernetes where a user that can create pods on Windows nodes may be able to escalate to admin privileges on those nodes. Kubernetes clusters are only affected if they include Windows nodes.

Kube-proxy on Windows can unintentionally forward traffic to local processes listening on the same port (“spec.ports[*].port”) as a LoadBalancer Service when the LoadBalancer controller does not set the “status.loadBalancer.ingress[].ip” field. Clusters where the LoadBalancer controller sets the “status.loadBalancer.ingress[].ip” field are unaffected.

Code injection via nginx.ingress.kubernetes.io/permanent-redirect annotation.

Privilege Escalation in kOps using GCE/GCP Provider in Gossip Mode.

A vulnerability was found in cri-o. This issue allows the addition of arbitrary lines into /etc/passwd by use of a specially crafted environment variable.

An authentication bypass vulnerability was discovered in kube-apiserver. This issue could allow a remote, authenticated attacker who has been given permissions "update, patch" the "pods/ephemeralcontainers" subresource beyond what the default is. They would then need to create a new pod or patch one that they already have access to. This might allow evasion of SCC admission restrictions, thereby gaining control of a privileged pod.

The version of cri-o as released for Red Hat OpenShift Container Platform 4.9.48, 4.10.31, and 4.11.6 via RHBA-2022:6316, RHBA-2022:6257, and RHBA-2022:6658, respectively, included an incorrect version of cri-o missing the fix for CVE-2022-27652, which was previously fixed in OCP 4.9.41 and 4.10.12 via RHBA-2022:5433 and RHSA-2022:1600. This issue could allow an attacker with access to programs with inheritable file capabilities to elevate those capabilities to the permitted set when execve(2) runs. For more details, see https://access.redhat.com/security/cve/CVE-2022-27652.

Users may be able to launch containers that bypass the mountable secrets policy enforced by the ServiceAccount admission plugin when using ephemeral containers. The policy ensures pods running with a service account may only reference secrets specified in the service account’s secrets field. Kubernetes clusters are only affected if the ServiceAccount admission plugin and the `kubernetes.io/enforce-mountable-secrets` annotation are used together with ephemeral containers.

A security issue was discovered in Kubelet that allows pods to bypass the seccomp profile enforcement. Pods that use localhost type for seccomp profile but specify an empty profile field, are affected by this issue. In this scenario, this vulnerability allows the pod to run in unconfined (seccomp disabled) mode. This bug affects Kubelet.

Kubernetes secrets-store-csi-driver in versions before 1.3.3 discloses service account tokens in logs.

This vulnerability exposes a network port in minikube running on macOS with Docker driver that could enable unexpected remote access to the minikube container.

Windows workloads can run as ContainerAdministrator even when those workloads set the runAsNonRoot option to true.

A security issue was discovered in ingress-nginx where a user that can create or update ingress objects can use a newline character to bypass the sanitization of the `spec.rules[].http.paths[].path` field of an Ingress object (in the `networking.k8s.io` or `extensions` API group) to obtain the credentials of the ingress-nginx controller. In the default configuration, that credential has access to all secrets in the cluster.

Users may have access to secure endpoints in the control plane network. Kubernetes clusters are only affected if an untrusted user can modify Node objects and send proxy requests to them. Kubernetes supports node proxying, which allows clients of kube-apiserver to access endpoints of a Kubelet to establish connections to Pods, retrieve container logs, and more. While Kubernetes already validates the proxying address for Nodes, a bug in kube-apiserver made it possible to bypass this validation. Bypassing this validation could allow authenticated requests destined for Nodes to to the API server's private network.

Incorrect handling of the supplementary groups in the CRI-O container engine might lead to sensitive information disclosure or possible data modification if an attacker has direct access to the affected container where supplementary groups are used to set access permissions and is able to execute a binary code in that container.

A security issue was discovered in aws-iam-authenticator where an allow-listed IAM identity may be able to modify their username and escalate privileges.

A vulnerability was found in CRI-O that causes memory or disk space exhaustion on the node for anyone with access to the Kube API. The ExecSync request runs commands in a container and logs the output of the command. This output is then read by CRI-O after command execution, and it is read in a manner where the entire file corresponding to the output of the command is read in. Thus, if the output of the command is large it is possible to exhaust the memory or the disk space of the node when CRI-O reads the output of the command. The highest threat from this vulnerability is system availability.

A security issue was discovered in ingress-nginx where a user that can create or update ingress objects can use the spec.rules[].http.paths[].path field of an Ingress object (in the networking.k8s.io or extensions API group) to obtain the credentials of the ingress-nginx controller. In the default configuration, that credential has access to all secrets in the cluster.

A flaw was found in cri-o, where containers were incorrectly started with non-empty default permissions. A vulnerability was found in Moby (Docker Engine) where containers started incorrectly with non-empty inheritable Linux process capabilities. This flaw allows an attacker with access to programs with inheritable file capabilities to elevate those capabilities to the permitted set when execve(2) runs.

A flaw was found in CRI-O in the way it set kernel options for a pod. This issue allows anyone with rights to deploy a pod on a Kubernetes cluster that uses the CRI-O runtime to achieve a container escape and arbitrary code execution as root on the cluster node, where the malicious pod was deployed.

An incorrect sysctls validation vulnerability was found in CRI-O 1.18 and earlier. The sysctls from the list of "safe" sysctls specified for the cluster will be applied to the host if an attacker is able to create a pod with a hostIPC and hostNetwork kernel namespace.

As mitigations to a report from 2019 and CVE-2020-8555, Kubernetes attempts to prevent proxied connections from accessing link-local or localhost networks when making user-driven connections to Services, Pods, Nodes, or StorageClass service providers. As part of this mitigation Kubernetes does a DNS name resolution check and validates that response IPs are not in the link-local (169.254.0.0/16) or localhost (127.0.0.0/8) range. Kubernetes then performs a second DNS resolution without validation for the actual connection. If a non-standard DNS server returns different non-cached responses, a user may be able to bypass the proxy IP restriction and access private networks on the control plane.

kubectl does not neutralize escape, meta or control sequences contained in the raw data it outputs to a terminal. This includes but is not limited to the unstructured string fields in objects such as Events.

A security issue was discovered in ingress-nginx where a user that can create or update ingress objects can use the custom snippets feature to obtain all secrets in the cluster.

Loading specially-crafted yaml with the Kubernetes Java Client library can lead to code execution.

A security issue was discovered in Kubernetes where a user may be able to create a container with subpath volume mounts to access files & directories outside of the volume, including on the host filesystem.

A security issue was discovered in kube-apiserver that could allow node updates to bypass a Validating Admission Webhook. Clusters are only affected by this vulnerability if they run a Validating Admission Webhook for Nodes that denies admission based at least partially on the old state of the Node object. Validating Admission Webhook does not observe some previous fields.

Kubernetes Java client libraries in version 10.0.0 and versions prior to 9.0.1 allow writes to paths outside of the current directory when copying multiple files from a remote pod which sends a maliciously crafted archive. This can potentially overwrite any files on the system of the process executing the client code.

Kubernetes CSI snapshot-controller prior to v2.1.3 and v3.0.2 could panic when processing a VolumeSnapshot custom resource when: - The VolumeSnapshot referenced a non-existing PersistentVolumeClaim and the VolumeSnapshot did not reference any VolumeSnapshotClass. - The snapshot-controller crashes, is automatically restarted by Kubernetes, and processes the same VolumeSnapshot custom resource after the restart, entering an endless crashloop. Only the volume snapshot feature is affected by this vulnerability. When exploited, users can’t take snapshots of their volumes or delete the snapshots. All other Kubernetes functionality is not affected.

Kubernetes Secrets Store CSI Driver versions v0.0.15 and v0.0.16 allow an attacker who can modify a SecretProviderClassPodStatus/Status resource the ability to write content to the host filesystem and sync file contents to Kubernetes Secrets. This includes paths under var/lib/kubelet/pods that contain other Kubernetes Secrets.

Kubernetes API server in all versions allow an attacker who is able to create a ClusterIP service and set the spec.externalIPs field, to intercept traffic to that IP address. Additionally, an attacker who is able to patch the status (which is considered a privileged operation and should not typically be granted to users) of a LoadBalancer service can set the status.loadBalancer.ingress.ip to similar effect.

In Kubernetes clusters using Ceph RBD as a storage provisioner, with logging level of at least 4, Ceph RBD admin secrets can be written to logs. This occurs in kube-controller-manager's logs during provisioning of Ceph RBD persistent claims. This affects < v1.19.3, < v1.18.10, < v1.17.13.