---
id: CVE-2026-47243
title: >-
  Kata Containers is an open source project focusing on a standard
  implementation of lightweight Virtual Machines (VMs) that perform like
  containers
summary: >-
  Kata Containers is an open source project focusing on a standard
  implementation of lightweight Virtual Machines (VMs) that perform like
  containers. Prior to 3.31.0, the runtime-rs standalone virtio-fs path is
  vulnerable to a guest-root t…
severity: critical
cvss: 9.2
cvssVector: 'CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:N/SC:H/SI:H/SA:N'
cwe:
  - CWE-22
  - CWE-36
vendor: kata-containers
product: kata-containers
affected:
  - kata-containers < 3.31.0
published: '2026-08-07'
updated: '2026-09-09'
sourceUpdated: '2026-09-09T21:02:22.660'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-47243'
references:
  - url: >-
      https://github.com/kata-containers/kata-containers/security/advisories/GHSA-2gv2-cffp-j227
    label: security-advisories@github.com
  - url: 'http://www.openwall.com/lists/oss-security/2026/05/21/14'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: >-
      https://github.com/kata-containers/kata-containers/security/advisories/GHSA-2gv2-cffp-j227
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
tags:
  - nvd
  - cve.org
  - exploit-available
exploitAvailable: true
ssvc:
  exploitation: poc
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-08-10T13:33:45.456561Z'
cvssSource: cna
ingestedAt: '2026-09-12T05:40:06.847Z'
epss: 0.00196
epssPercentile: 0.08248
---

## Overview

Kata Containers is an open source project focusing on a standard implementation of lightweight Virtual Machines (VMs) that perform like containers. Prior to 3.31.0, the runtime-rs standalone virtio-fs path is vulnerable to a guest-root to host-root escape. In this configuration, Kata runs the host virtiofsd as root with --sandbox none --seccomp none, so an attacker with root-equivalent access inside the guest can bypass the guest virtio-fs client entirely by taking over the virtio-fs PCI device and building a virtqueue in userspace to submit raw FUSE requests directly to the host virtiofsd. A crafted FUSE_SYMLINK request whose new symlink name is an absolute host path is honored outside the configured shared directory, allowing guest root to create root-owned symlinks in sensitive host locations such as /etc/cron.d. By pointing such a symlink at a guest-controlled crontab payload reachable through a live runtime process's mount namespace, the attacker causes the host cron daemon to execute that payload as host root, crossing the Kata isolation boundary. This issue is fixed in version 3.31.0.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.