KubeVirt Arbitrary Container File Read
Date: 2025-11
Affected: go/kubevirt.io/kubevirt, go/kubevirt.io/kubevirt
Attack vector: path-traversal
Category: vulnerability-disclosure
Severity: Medium
CVE: CVE-2025-64433
CWE: CWE-22
CVSS: 6.5 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N)

### 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


Mitigations:

Architectural layers (MAESTRO):