> For the complete documentation index, see [llms.txt](https://docs.ionos.com/cloud/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.ionos.com/cloud/security-safeguards/vulnerability-register/2026/ubuntu-crack-armor-vulnerability.md).

# Advisory on CrackArmor Vulnerability

On March 19, 2026, Ubuntu disclosed several vulnerabilities affecting Managed Kubernetes node images.

These vulnerabilities, known collectively as CrackArmor, allow an attacker with code execution inside a container running on an affected node to escape the container boundary. The attacker could then gain access to the underlying host operating system.

These vulnerabilities are classified as **High** severity with the following CVSS scores:

| CVE ID                                                                                        | CVSS Score |
| --------------------------------------------------------------------------------------------- | :--------: |
| [<mark style="color:blue;">CVE-2026-23268</mark>](https://ubuntu.com/security/CVE-2026-23268) |     7.8    |
| [<mark style="color:blue;">CVE-2026-23269</mark>](https://ubuntu.com/security/CVE-2026-23269) |     7.1    |
| [<mark style="color:blue;">CVE-2026-23406</mark>](https://ubuntu.com/security/CVE-2026-23406) |     7.8    |
| [<mark style="color:blue;">CVE-2026-23407</mark>](https://ubuntu.com/security/CVE-2026-23407) |     7.8    |
| [<mark style="color:blue;">CVE-2026-23408</mark>](https://ubuntu.com/security/CVE-2026-23408) |     7.8    |
| [<mark style="color:blue;">CVE-2026-23410</mark>](https://ubuntu.com/security/CVE-2026-23410) |     7.8    |
| [<mark style="color:blue;">CVE-2026-23411</mark>](https://ubuntu.com/security/CVE-2026-23411) |     7.8    |

## Impacted IONOS CLOUD products

| Product Ranges | Product                                                                                        | Impacted | Mitigated | Patch Status |
| -------------- | ---------------------------------------------------------------------------------------------- | -------- | --------- | ------------ |
| Containers     | [<mark style="color:blue;">Managed Kubernetes</mark>](/cloud/containers/managed-kubernetes.md) | Yes      | Yes       | Done         |

## Risk on IONOS CLOUD user environment

Workloads running in containers on affected Managed Kubernetes nodes were at risk of container escape. An attacker with code execution inside a container could potentially break out to the host node and access resources outside their intended boundary.

## What action has IONOS CLOUD taken to mitigate the vulnerability?

<code class="expression">space.vars.ionos\_cloud</code> has applied updated Managed Kubernetes node images across all regions.

## What action can you take to mitigate the vulnerability?

No action is required. Updated node images are applied automatically during your node pool's scheduled maintenance window.

## How can I get help?

If you have further questions or concerns about this vulnerability, contact [<mark style="color:blue;">IONOS CLOUD Support</mark>](https://docs.ionos.com/support/general-information/contact-information).


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