# GHSA-xx64-wwv2-hcqq: astral-tokio-tar: `unpack_in` can chmod arbitrary directories by following symlinks

> An attacker can craft a tar archive to change permissions of arbitrary directories outside the extraction path via symlink traversal.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 27 Apr 2026
- **Also known as:** RUSTSEC-2026-0113

## What is GHSA-xx64-wwv2-hcqq?

GHSA-xx64-wwv2-hcqq is a path traversal vulnerability in astral-tokio-tar, published on 27 Apr 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.

### Official description

### Impact

In versions 0.6.0 and earlier of astral-tokio-tar, the `unpack_in` API could inadvertently modify the permissions of external (i.e. non-archive) directories outside of the archive. An attacker could use this to contrite a tar archive that maliciously changes directory permissions outside of its intended hierarchy. This flaw only affects directories; individual file permissions cannot be modified via it.

See GHSA-j4xf-2g29-59ph for the equivalent flaw in the `tar` crate.

### Patches

Versions 0.6.1 and newer of astral-tokio-tar use `fs::symlink_metdata` rather than `fs::metadata`, avoiding the traversal. 

### Workarounds

Users are advised to upgrade to version 0.6.1 or newer to address this advisory.

Users should experience no breaking changes as a result of the patch above.

### Resources

- GHSA-j4xf-2g29-59ph for the original `tar` vulnerability

### Attribution

- Reporter: Adam Harvey (@lawngnome)

## Which versions are affected by GHSA-xx64-wwv2-hcqq?

3 open source packages ship an affected version, including astral-tokio-tar.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `astral-tokio-tar` | crates.io | All versions | 0.6.1 |
| `astral-tokio-tar` | crates.io | All versions | 0.6.1 |
| `astral-tokio-tar` | crates.io | From 0.0.0-0 | 0.6.1 |

## How do I fix GHSA-xx64-wwv2-hcqq?

Upgrade astral-tokio-tar to 0.6.1 or later.

## Is GHSA-xx64-wwv2-hcqq being exploited?

There is no known exploitation of GHSA-xx64-wwv2-hcqq in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for GHSA-xx64-wwv2-hcqq and fix it if it is affected.

What it is: GHSA-xx64-wwv2-hcqq is a path traversal vulnerability in astral-tokio-tar, published on 27 Apr 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of GHSA-xx64-wwv2-hcqq in the wild and no public exploit code.

Affected packages and fixed versions:
- astral-tokio-tar (crates.io): affected all versions; fixed in 0.6.1
- astral-tokio-tar (crates.io): affected all versions; fixed in 0.6.1
- astral-tokio-tar (crates.io): affected from 0.0.0-0; fixed in 0.6.1

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/GHSA-xx64-wwv2-hcqq/ (Markdown: https://insights.sbomify.com/GHSA-xx64-wwv2-hcqq/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/GHSA-xx64-wwv2-hcqq

---
From sbomify Insights: https://insights.sbomify.com/GHSA-xx64-wwv2-hcqq/
Summaries are generated and may contain mistakes; the official description above is the record.