# CVE-2020-29480: Information disclosure in n/a

> A guest administrator can observe non-sensitive lifecycle events and configuration details of other virtual machines due to missing permission checks in Xenstore watch events.

- **Severity:** Low 2.3 (`CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:L/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 15 Dec 2020
- **Updated:** 4 Aug 2024
- **Also known as:** ALPINE-CVE-2020-29480, DEBIAN-CVE-2020-29480, GHSA-h88c-j84g-842h, UBUNTU-CVE-2020-29480

## What is CVE-2020-29480?

CVE-2020-29480 is a low-severity vulnerability in Debian Debian Linux, published on 15 Dec 2020. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

An issue was discovered in Xen through 4.14.x. Neither xenstore implementation does any permission checks when reporting a xenstore watch event. A guest administrator can watch the root xenstored node, which will cause notifications for every created, modified, and deleted key. A guest administrator can also use the special watches, which will cause a notification every time a domain is created and destroyed. Data may include: number, type, and domids of other VMs; existence and domids of driver domains; numbers of virtual interfaces, block devices, vcpus; existence of virtual framebuffers and their backend style (e.g., existence of VNC service); Xen VM UUIDs for other domains; timing information about domain creation and device setup; and some hints at the backend provisioning of VMs and their devices. The watch events do not contain values stored in xenstore, only key names. A guest administrator can observe non-sensitive domain and device lifecycle events relating to other guests. This information allows some insight into overall system configuration (including the number and general nature of other guests), and configuration of other guests (including the number and general nature of other guests' devices). This information might be commercially interesting or might make other attacks easier. There is not believed to be exposure of sensitive data. Specifically, there is no exposure of VNC passwords, port numbers, pathnames in host and guest filesystems, cryptographic keys, or within-guest data.

Weakness: CWE-862 (Missing Authorization)

## Which versions are affected by CVE-2020-29480?

It affects 3 products.


Products: Debian Debian Linux, Fedoraproject Fedora, Xen Xen.

## How do I fix CVE-2020-29480?

Apply the vendor's patch.

## Is CVE-2020-29480 being exploited?

There is no known exploitation of CVE-2020-29480 in the wild and no public exploit code.

## Other vulnerabilities in Debian Debian Linux

- [CVE-2015-3306](https://insights.sbomify.com/CVE-2015-3306/): ProFTPD Improper Access Control (critical 10.0, exploited in the wild)
- [CVE-2025-49113](https://insights.sbomify.com/CVE-2025-49113/): RoundCube Webmail Deserialization of Untrusted Data (critical 9.9, exploited in the wild)
- [CVE-2026-24061](https://insights.sbomify.com/CVE-2026-24061/): GNU InetUtils Argument Injection (critical 9.8, exploited in the wild)
- [CVE-2025-39682](https://insights.sbomify.com/CVE-2025-39682/): Linux Kernel Improper Check for Unusual or Exceptional Conditions (critical 9.8, exploited in the wild)
- [CVE-2024-9680](https://insights.sbomify.com/CVE-2024-9680/): Mozilla Firefox Use-After-Free (critical 9.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-29480 and fix it if it is affected.

What it is: CVE-2020-29480 is a low-severity vulnerability in Debian Debian Linux, published on 15 Dec 2020. 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-2020-29480 in the wild and no public exploit code.

Affected product: Debian Debian Linux. 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-2020-29480/ (Markdown: https://insights.sbomify.com/CVE-2020-29480/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-29480
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-29480
- OSV: https://osv.dev/vulnerability/CVE-2020-29480

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-29480/
Summaries are generated and may contain mistakes; the official description above is the record.
