A flaw was found in kubevirt 0.29 and earlier. Virtual Machine Instances (VMIs) can be used to gain access to the host's filesystem. Successful exploitation allows an attacker to assume the privileges of the VM process on the host system. In worst-case scenarios an attacker can read and modify any file on the system where the VMI is running. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.
FakeFish handles incoming credentials by passing them down to scripts. This works for real hardware because in the end it's up to the BMC to validate them. However, KubeVirt relies on a KUBECONFIG file mounted to the container and completely ignores the credentials. This allows any user of the cluster to control VMs of the user that created fakefish, power them on and off, and mount arbitrary CD images to them.
A path traversal vulnerability in KubeVirt versions up to 0.56 (and 0.55.1) on all platforms allows a user able to configure the kubevirt to read arbitrary files on the host filesystem which are publicly readable or which are readable for UID 107 or GID 107. /proc/self/<> is not accessible.
A flaw was found in the KubeVirt main virt-handler versions before 0.26.0 regarding the access permissions of virt-handler. An attacker with access to create VMs could attach any secret within their namespace, allowing them to read the contents of that secret.
A flaw was found in KubeVirt's network annotation generator. The tenant-supplied multus.networkName in a VMI spec is written verbatim into the launcher pod's v1.multus-cni.io/default-network annotation without input validation. When the ExternalNetResourceInjection Beta feature gate is enabled (off by default), no NAD lookup is performed to catch malformed values, and a tenant can inject a JSON-formatted NetworkSelectionElement array to attach the pod to arbitrary network attachments in any namespace with attacker-controlled IP and MAC addresses. This enables cross-namespace network access and service impersonation. The vulnerable code path was introduced with the ExternalNetResourceInjection feature gate in KubeVirt v1.8.0, first shipped in OpenShift Virtualization 4.21.
A flaw was found in KubeVirt's downward metrics virtio-serial server in virt-handler. The server reads guest requests using textproto.Reader.ReadLine() in pkg/downwardmetrics/virtio-serial/server.go, which buffers input indefinitely until a newline character is received, with no length limit or read deadline. The server is started from dmetrics-manager.go and wired into the virt-handler process at cmd/virt-handler/virt-handler.go — it runs inside virt-handler's address space, not in the per-VM virt-launcher pod. A VM guest writing a continuous byte stream without newlines to the downward-metrics virtio-serial channel causes unbounded heap allocation in virt-handler until it is OOM-killed. Affected image: virt-handler-rhel9. Upstream fix should wrap the reader in io.LimitedReader with a small cap and add a per-read deadline.
A flaw was found in KubeVirt's downward metrics virtio-serial server in virt-handler. The server reads guest requests using textproto.Reader.ReadLine() in pkg/downwardmetrics/virtio-serial/server.go, which buffers input indefinitely until a newline character is received, with no length limit or read deadline. The server is started from dmetrics-manager.go and wired into the virt-handler process at cmd/virt-handler/virt-handler.go — it runs inside virt-handler's address space, not in the per-VM virt-launcher pod. A VM guest writing a continuous byte stream without newlines to the downward-metrics virtio-serial channel causes unbounded heap allocation in virt-handler until it is OOM-killed. Affected image: virt-handler-rhel9. Upstream fix should wrap the reader in io.LimitedReader with a small cap and add a per-read deadline.