# CVE-2026-13322: Kubevirt: virt-handler-rhel9: kubevirt: unbounded virtio-serial readline in virt-handler causes oom denial of service

> An attacker with guest access can cause a denial of service in virt-handler by sending unbounded data to the virtio-serial device, leading to memory exhaustion.

- **Severity:** Low 3.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 26 Jun 2026
- **Updated:** 26 Jun 2026
- **Also known as:** AZL-91454, GHSA-6f2p-2qg2-qqch, MINI-2fvj-hmpf-r7f4, MINI-5p38-r9qp-8p5h

## What is CVE-2026-13322?

CVE-2026-13322 is a low-severity denial of service vulnerability in Red Hat OpenShift Virtualization 4, published on 26 Jun 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A flaw was found in KubeVirt's downward metrics virtio-serial server. The server reads guest requests using textproto.Reader.ReadLine(), which buffers input indefinitely until a newline character is received, with no length limit or read deadline. A user with access to a VM guest that has the downward metrics virtio-serial device configured can write a continuous byte stream to the device, causing unbounded memory allocation in the virt-handler process until it is OOM-killed.

Weakness: CWE-770 (Allocation of Resources Without Limits or Throttling)

## Which versions are affected by CVE-2026-13322?

It affects 2 products.


Products: Kubevirt Kubevirt, Redhat Openshift Virtualization.

## How do I fix CVE-2026-13322?

No fix has been published for CVE-2026-13322 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-13322 being exploited?

There is no known exploitation of CVE-2026-13322 in the wild and no public exploit code.

## Other vulnerabilities in Red Hat OpenShift Virtualization 4

- [CVE-2020-14316](https://insights.sbomify.com/CVE-2020-14316/): Privilege Escalation in kubevirt (critical 9.9)
- [CVE-2022-1798](https://insights.sbomify.com/CVE-2022-1798/): Path Traversal vulnerability in Kubevirt (high 8.7)
- [CVE-2025-64324](https://insights.sbomify.com/CVE-2025-64324/): KubeVirt Vulnerable to Arbitrary Host File Read and Write (high 8.5)
- [CVE-2023-26484](https://insights.sbomify.com/CVE-2023-26484/): On a compromised KubeVirt node, the virt-handler service account can be used to modify all node specs (high 8.2)
- [CVE-2026-13201](https://insights.sbomify.com/CVE-2026-13201/): Path traversal in Red Hat Container Native Virtualization 4.12 (high 7.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-13322 and fix it if it is affected.

What it is: CVE-2026-13322 is a low-severity denial of service vulnerability in Red Hat OpenShift Virtualization 4, published on 26 Jun 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-13322 in the wild and no public exploit code.

Affected product: Red Hat OpenShift Virtualization 4. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-13322/ (Markdown: https://insights.sbomify.com/CVE-2026-13322/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-13322
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-13322
- OSV: https://osv.dev/vulnerability/CVE-2026-13322

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-13322/
Summaries are generated and may contain mistakes; the official description above is the record.