# CVE-2021-3631: Privilege escalation in libvirt

> A flaw in libvirt allows a compromised guest VM to access files of another guest, breaking sVirt confinement and compromising confidentiality and integrity.

- **Severity:** Medium 6.3 (`CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N`)
- **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:** Yes
- **Published:** 2 Mar 2022
- **Updated:** 19 Nov 2024
- **Also known as:** DEBIAN-CVE-2021-3631, GHSA-4225-xq9f-4ww3, MGASA-2021-0399, SUSE-SU-2021:2471-1, UBUNTU-CVE-2021-3631, openSUSE-SU-2021:1119-1

## What is CVE-2021-3631?

CVE-2021-3631 is a medium-severity vulnerability in Netapp Ontap Select Deploy Administration Utility, published on 2 Mar 2022. 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 libvirt while it generates SELinux MCS category pairs for VMs' dynamic labels. This flaw allows one exploited guest to access files labeled for another guest, resulting in the breaking out of sVirt confinement. The highest threat from this vulnerability is to confidentiality and integrity.

Weakness: CWE-732 (Incorrect Permission Assignment for Critical Resource)

## Which versions are affected by CVE-2021-3631?

It affects 4 products.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `libvirt` | SUSE:Linux Enterprise Micro 5.0 | All versions | 6.0.0-13.16.2 |
| `libvirt` | SUSE:Linux Enterprise Module for Basesystem 15 SP2 | All versions | 6.0.0-13.16.2 |
| `libvirt` | SUSE:Linux Enterprise Module for Server Applications 15 SP2 | All versions | 6.0.0-13.16.2 |
| `libvirt` | openSUSE:Leap 15.2 | All versions | 6.0.0-lp152.9.12.1 |

Products: Netapp Ontap Select Deploy Administration Utility, Redhat Enterprise Linux, Redhat Libvirt, Redhat Openshift Container Platform.

## How do I fix CVE-2021-3631?

Apply the vendor's patch.

## Is CVE-2021-3631 being exploited?

There is no known exploitation of CVE-2021-3631 in the wild and no public exploit code.

## Other vulnerabilities in Netapp Ontap Select Deploy Administration Utility

- [CVE-2020-35527](https://insights.sbomify.com/CVE-2020-35527/): Memory corruption in sqlite (critical 9.8)
- [CVE-2020-11656](https://insights.sbomify.com/CVE-2020-11656/): Use after free in n/a (critical 9.8)
- [CVE-2019-5509](https://insights.sbomify.com/CVE-2019-5509/): Code injection in ONTAP Select Deploy administration utility (critical 9.8)
- [CVE-2019-5504](https://insights.sbomify.com/CVE-2019-5504/): Missing authorization in ONTAP Select Deploy administration utility (critical 9.8)
- [CVE-2019-5505](https://insights.sbomify.com/CVE-2019-5505/): Information disclosure in ONTAP Select Deploy administration utility (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-3631 and fix it if it is affected.

What it is: CVE-2021-3631 is a medium-severity vulnerability in Netapp Ontap Select Deploy Administration Utility, published on 2 Mar 2022. 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-2021-3631 in the wild and no public exploit code.

Affected product: Netapp Ontap Select Deploy Administration Utility. 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-2021-3631/ (Markdown: https://insights.sbomify.com/CVE-2021-3631/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-3631
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-3631
- OSV: https://osv.dev/vulnerability/CVE-2021-3631

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-3631/
Summaries are generated and may contain mistakes; the official description above is the record.