Microsoft security update for CVE-2026-47243
🔗 CVE IDs covered (1)
📋 Microsoft's advisory
EchelonGraph does not copy Microsoft's advisory page: its FAQ and remediation text are not shown here. Read the advisory on https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-47243. This page also shows what EchelonGraph holds for CVE-2026-47243, with the description from its CVE record, which the CVE Numbering Authority that assigned the CVE wrote: for a CVE Microsoft assigned, often in the words of Microsoft's own advisory.
🎯 Affected products1
- azl3 kata-containers 3.19.1.kata3-7 on Azure Linux 3.0
✅ Updates Microsoft lists: 1 update
1 row: one per KB article or update, update type and fixed build. Their details are on Microsoft's advisory.
| KB article | Update | Fixed build |
|---|---|---|
| — | Security Update | 3.32.0.kata0-1 |
🧭 EchelonGraph on CVE-2026-47243
- EchelonGraph score
- 9.2 CRITICAL
- CISA KEV
- Not listed
- Fix status
- A fix is available — apply it.
Description from the CVE record (CVE.org), as published by its numbering authority
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.
Published by GitHub, Inc., the CVE Numbering Authority that assigned CVE-2026-47243, in its CVE record at CVE.org; reused under the CVE Program's Terms of Use (its licence and MITRE's copyright notice are in our Terms of Service).