CVE-2026-13318

Summary

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.

Affected Software

VendorProductVersion RangeStatus

Weaknesses

  • CWE-918: Server-Side Request Forgery (SSRF)

Workarounds

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.

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: partial

References