# CVE-2026-45405: Dokku: Arbitrary File Write via Tar Symlink Traversal in git:from-archive and certs:add

> Attackers can write arbitrary files via symlink traversal in archive extraction, potentially overwriting SSH keys to gain shell access on Dokku servers.

- **Severity:** Critical 9.0 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:R/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:** A user has to click or open something
- **Fix available:** No
- **Published:** 26 Jun 2026
- **Updated:** 26 Jun 2026
- **Also known as:** GHSA-j6qq-xg73-ghqg

## What is CVE-2026-45405?

CVE-2026-45405 is a critical path traversal vulnerability in dokku, published on 26 Jun 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.

### Official description

Dokku is a docker-powered PaaS. Prior to 0.38.2, the git:from-archive and certs:add commands extract user-supplied tar/zip archives into temporary directories without sanitizing member paths or preventing symlink traversal. GNU tar creates symlinks during extraction and follows them for subsequent entries, allowing an attacker to write arbitrary files anywhere writable by the dokku user — including overwriting ~/.ssh/authorized_keys to gain unrestricted shell access. This vulnerability is fixed in 0.38.2.

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

## Which versions are affected by CVE-2026-45405?

It affects 1 product.


Products: Dokku Dokku.

## How do I fix CVE-2026-45405?

No fix has been published for CVE-2026-45405 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-45405 being exploited?

There is no known exploitation of CVE-2026-45405 in the wild and no public exploit code.

## Other vulnerabilities in dokku

- [CVE-2026-45406](https://insights.sbomify.com/CVE-2026-45406/): Dokku: Host RCE via Maliciously Named OpenResty Include Files Injected Through eval (critical 9.0)
- [CVE-2026-45408](https://insights.sbomify.com/CVE-2026-45408/): Dokku: OS Command Injection via App Name in Git Pre-Receive Hook (critical 9.0)
- [CVE-2026-54636](https://insights.sbomify.com/CVE-2026-54636/): Dokku: OS Command Injection via app.json managed Cron (critical 9.0)
- [CVE-2026-45407](https://insights.sbomify.com/CVE-2026-45407/): Dokku: Git Credentials in .netrc Stored World-Readable Due to Premature touch (medium 5.0)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-45405 and fix it if it is affected.

What it is: CVE-2026-45405 is a critical path traversal vulnerability in dokku, published on 26 Jun 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2026-45405 in the wild and no public exploit code.

Affected product: dokku. 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-2026-45405/ (Markdown: https://insights.sbomify.com/CVE-2026-45405/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-45405
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-45405
- OSV: https://osv.dev/vulnerability/CVE-2026-45405

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-45405/
Summaries are generated and may contain mistakes; the official description above is the record.