# CVE-2026-63294: Root RCE via image backup.yaml symlink

> Attackers can execute arbitrary commands with root privileges on the host by exploiting symlink handling in LXD image backups.

- **Severity:** Critical 9.9 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 12 Aug 2026
- **Updated:** 13 Aug 2026
- **Also known as:** DEBIAN-CVE-2026-63294, GHSA-fv82-v4fj-mm4m, UBUNTU-CVE-2026-63294

## What is CVE-2026-63294?

CVE-2026-63294 is a critical path traversal vulnerability in Canonical LXD, published on 12 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

A link following vulnerability in LXD allows an attacker to achieve root command execution on the host system. During the import or unpacking of crafted image or backup archives, LXD fails to properly validate and confine the backup.yaml file when it exists as a symbolic link. An attacker can exploit this flaw by providing a malicious archive with a symlinked backup.yaml file, causing LXD to process unconfined configuration metadata and execute arbitrary commands with root privileges.

Weakness: CWE-59 (Improper Link Resolution Before File Access)

## Which versions are affected by CVE-2026-63294?

It affects 1 product.


Products: Canonical Lxd.

## How do I fix CVE-2026-63294?

No fix has been published for CVE-2026-63294 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-63294 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-63294 exists.

## Other vulnerabilities in Canonical LXD

- [CVE-2026-66897](https://insights.sbomify.com/CVE-2026-66897/): Instance template path traversal allows arbitrary host file write as root (critical 9.9)
- [CVE-2026-62420](https://insights.sbomify.com/CVE-2026-62420/): Cross-project cluster migration bypasses project restrictions via cluster notification flag (critical 9.9)
- [CVE-2026-63293](https://insights.sbomify.com/CVE-2026-63293/): Arbitrary File Read/Write: metadata.yaml symlink in image allows host filesystem access as root (critical 9.9)
- [CVE-2026-63296](https://insights.sbomify.com/CVE-2026-63296/): Project restriction bypass via instance migration config override (critical 9.9)
- [CVE-2026-63297](https://insights.sbomify.com/CVE-2026-63297/): Cross-project instance copy bypasses target project restrictions via TOCTOU in config merge (critical 9.9)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-63294 and fix it if it is affected.

What it is: CVE-2026-63294 is a critical path traversal vulnerability in Canonical LXD, published on 12 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-63294 exists.

Affected product: Canonical LXD. 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-2026-63294/ (Markdown: https://insights.sbomify.com/CVE-2026-63294/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-63294
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-63294
- OSV: https://osv.dev/vulnerability/CVE-2026-63294

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-63294/
Summaries are generated and may contain mistakes; the official description above is the record.