SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2023-26484

In versions 0.59.0 and prior, if a malicious user has taken over a Kubernetes node where virt-handler (the KubeVirt node-daemon) is running, the virt-handler service account can be used to modify all node specs.

HIGH 8.2EPSS 0.61%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.61%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

KubeVirt is a virtual machine management add-on for Kubernetes. In versions 0.59.0 and prior, if a malicious user has taken over a Kubernetes node where virt-handler (the KubeVirt node-daemon) is running, the virt-handler service account can be used to modify all node specs. This can be misused to lure-in system-level-privileged components which can, for instance, read all secrets on the cluster, or can exec into pods on other nodes. This way, a compromised node can be used to elevate privileges beyond the node until potentially having full privileged access to the whole cluster. The simplest way to exploit this, once a user could compromise a specific node, is to set with the virt-handler service account all other nodes to unschedulable and simply wait until system-critical components with high privileges appear on its node. No patches are available as of time of publication. As a workaround, gatekeeper users can add a webhook which will block the `virt-handler` service account to modify the spec of a node.

CVSS 3.1
8.2 HIGHCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:N
EPSS
0.61% probability · 47th percentile
CISA KEV
Not listed
Weakness
CWE-863
Affected
kubevirt/kubevirt
Source
security-advisories@github.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.