Copyright © 2012 Red Hat, Inc. All rights reserved. Moderate 2026-06-25T00:00:00 virt-api-rhel9: kubevirt: KubeVirt: SSRF in virt-api port-forward via unvalidated guest-agent-reported IP 6.4 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N CWE-918

A server-side request forgery (SSRF) flaw was found in KubeVirt's virt-api port-forward handler. When processing a port-forward request to a VirtualMachineInstance (VMI), virt-api reads the target IP from vmi.Status.Interfaces[0].IP and passes it directly to net.Dial() without validation. For VMIs using non-masquerade network bindings (bridge or secondary-only), this IP is reported by the QEMU guest agent running inside the VM and is fully controllable by the VM owner. An attacker with kubevirt.io:edit permissions can create a VM with a modified guest agent that reports an arbitrary IP address, then request port-forward to establish a bidirectional TCP tunnel from virt-api's cluster-internal network position to any routable destination, bypassing NetworkPolicy isolation.

A server-side request forgery (SSRF) flaw was found in KubeVirt's virt-api port-forward handler. When processing a port-forward request to a VirtualMachineInstance (VMI), virt-api reads the target IP from vmi.Status.Interfaces[0].IP and passes it directly to net.Dial() without validation. For VMIs using non-masquerade network bindings (bridge or secondary-only), this IP is reported by the QEMU guest agent running inside the VM and is fully controllable by the VM owner. An attacker with kubevirt.io:edit permissions can create a VM with a modified guest agent that reports an arbitrary IP address, then request port-forward to establish a bidirectional TCP tunnel from virt-api's cluster-internal network position to any routable destination, bypassing NetworkPolicy isolation.

Red Hat has rated this issue as Moderate impact. Only VMs configured with bridge binding or secondary-only network interfaces (which require a cluster administrator to have created a NetworkAttachmentDefinition) are affected. This issue was discovered by Huzaifa Sidhpurwala (Red Hat). Users who do not use bridge binding or secondary-only network interfaces for their VMs are not affected by this vulnerability. For environments using these configurations, cluster administrators can apply egress NetworkPolicy to the openshift-cnv namespace to restrict virt-api's outbound connections to known-legitimate destinations (launcher pod CIDRs and node IPs), which blocks the SSRF to arbitrary targets. Red Hat OpenShift Virtualization 4 Fix deferred container-native-virtualization/virt-api Red Hat OpenShift Virtualization 4 Fix deferred container-native-virtualization/virt-api-rhel9 https://www.cve.org/CVERecord?id=CVE-2026-13318 https://nvd.nist.gov/vuln/detail/CVE-2026-13318