# CVE-2026-64825: Home Assistant Core < 2026.6.0 Path Traversal File Write via Backup Upload

> Unauthenticated attackers can write arbitrary files to the host filesystem via a crafted backup upload during onboarding, potentially achieving code execution.

- **Severity:** Critical 9.0 (`CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:L/SC:N/SI:H/SA:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 21 Jul 2026
- **Updated:** 8 Oct 2026
- **Also known as:** GHSA-5hxg-r395-fqxx, PYSEC-2026-3669

## What is CVE-2026-64825?

CVE-2026-64825 is a critical path traversal vulnerability in home-assistant Home Assistant Core, published on 21 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Home Assistant Core before 2026.6.0 contains a path traversal vulnerability that allows unauthenticated attackers to write arbitrary files to any directory on the host filesystem by uploading a crafted backup archive during the initial onboarding window. Attackers can manipulate the 'name' field inside the uploaded archive's backup.json to supply an absolute path, causing pathlib.Path.__truediv__ to discard the configured backup directory prefix and write attacker-controlled content to arbitrary locations, with full filesystem access when the process runs as root.

Weakness: CWE-22 (Improper Limitation of a Pathname to a Restricted Directory)

## Which versions are affected by CVE-2026-64825?

3 open source packages ship an affected version, including homeassistant.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `homeassistant` | PyPI | All versions | 2026.6.0 |
| `homeassistant` | PyPI | All versions | 2026.6.0 |
| `homeassistant` | PyPI | All versions | 2026.6.0 |

## How do I fix CVE-2026-64825?

Upgrade homeassistant to 2026.6.0 or later.

## Is CVE-2026-64825 being exploited?

There is no known exploitation of CVE-2026-64825 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-64825 and fix it if it is affected.

What it is: CVE-2026-64825 is a critical path traversal vulnerability in home-assistant Home Assistant Core, published on 21 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-64825 in the wild and no public exploit code.

Affected packages and fixed versions:
- homeassistant (PyPI): affected all versions; fixed in 2026.6.0
- homeassistant (PyPI): affected all versions; fixed in 2026.6.0
- homeassistant (PyPI): affected all versions; fixed in 2026.6.0

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-2026-64825/ (Markdown: https://insights.sbomify.com/CVE-2026-64825/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-64825
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-64825
- OSV: https://osv.dev/vulnerability/CVE-2026-64825

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-64825/
Summaries are generated and may contain mistakes; the official description above is the record.