CVE-2026-13434 Missing authorization in Red Hat OpenShift Virtualization 4
Tenants can inject network annotations to access other namespaces and impersonate IPs when a specific feature gate is enabled.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-13434?
CVE-2026-13434 is a medium-severity missing authorization vulnerability in Red Hat OpenShift Virtualization 4, published on 26 Jun 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
A flaw was found in KubeVirt's network annotation generator. When a tenant creates a VirtualMachineInstance with a Multus network configuration, the supplied networkName value is written verbatim into the launcher pod's v1.multus-cni.io/default-network annotation without format validation or sanitization. The only admission check rejects empty strings; no DNS-1123 format validation, JSON detection, or special character rejection is performed. When the ExternalNetResourceInjection Beta feature gate is enabled (off by default, cluster-admin only), the NAD lookup that would otherwise catch malformed names is skipped by design. A tenant with kubevirt.io:edit permissions can inject a JSON-formatted NetworkSelectionElement array specifying an arbitrary namespace, NAD name, static IP address, and MAC address. Multus on the node parses this JSON and attaches the launcher pod to the specified network attachment in any namespace, enabling cross-namespace network access and IP/MAC impersonation on network segments normally segregated from tenant workloads. The ExternalNetResourceInjection feature gate was introduced in KubeVirt v1.8.0 (first shipped in OpenShift Virtualization 4.21).
Weakness: CWE-20
Which versions are affected by CVE-2026-13434?
It affects 2 products.
Products include Kubevirt Kubevirt, Redhat Openshift Virtualization.
How do I fix CVE-2026-13434?
No fix has been published for CVE-2026-13434 yet. Limit exposure of the affected software until one is available.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-13434 being exploited?
There is no known exploitation of CVE-2026-13434 in the wild and no public exploit code.
Other vulnerabilities in Red Hat OpenShift Virtualization 4
- CVE-2020-14316 Privilege Escalation in kubevirt
- CVE-2022-1798 Path Traversal vulnerability in Kubevirt
- CVE-2025-64324 KubeVirt Vulnerable to Arbitrary Host File Read and Write
- CVE-2023-26484 On a compromised KubeVirt node, the virt-handler service account can be used to modify all node specs
- CVE-2026-13201 Path traversal in Red Hat Container Native Virtualization 4.12
Sources
Also known as GHSA-9fjc-whw6-cqfc, MINI-fpm5-fhwg-8854, MINI-xffh-2665-387g.