# CVE-2025-62518: RUSTSEC-2025-0110 - astral-tokio-tar Vulnerable to PAX Header Desynchronization

Source: https://junglewise.ai/threats/cve-2025-62518-astral-tokio-tar-vulnerable-to-pax-header-desynchronization  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2025-10-21  
License: CC BY 4.0 with a link back

CVE-2025-62518 · Severity: high · CVSS 8.1 · Published 2025-10-21

astral-tokio-tar is a tar archive reading/writing library for async Rust. Versions of astral-tokio-tar prior to 0.5.6 contain a boundary parsing vulnerability that allows attackers to smuggle additional archive entries by exploiting inconsistent PAX/ustar header handling. When processing archives with PAX-extended headers containing size overrides, the parser incorrectly advances stream position based on ustar header size (often zero) instead of the PAX-specified size, causing it to interpret file content as legitimate tar headers. This issue has been patched in version 0.5.6. There are no workarounds.

Technologies: [astral-tokio-tar (crates.io)](https://junglewise.ai/threats/technologies/astral-tokio-tar). Vendors: [crates.io](https://junglewise.ai/threats/vendors/crates-io).

## Quick answers

**Is CVE-2025-62518 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2025-62518 being exploited in the wild.

**How severe is CVE-2025-62518?** High severity, with a CVSS score of 8.1, published 21 October 2025.

**Which products and versions are affected?** astral-tokio-tar (crates.io) SEMVER:introduced=0,fixed=0.5.6, SEMVER:introduced=0.0.0-0,fixed=0.5.6; tokio-tar (crates.io) SEMVER:introduced=0,last_affected=0.3.1, SEMVER:introduced=0.0.0-0.

**Is there a fix for CVE-2025-62518?** Yes. astral-tokio-tar (crates.io): upgrade to 0.5.6 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected by CVE-2025-62518?** Check whether you run astral-tokio-tar (crates.io) or tokio-tar (crates.io) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- astral-tokio-tar (crates.io): upgrade to 0.5.6 or later

  ```sh
  cargo update -p astral-tokio-tar
  ```


## Affected products

- astral-tokio-tar (crates.io) SEMVER:introduced=0,fixed=0.5.6, SEMVER:introduced=0.0.0-0,fixed=0.5.6
- tokio-tar (crates.io) SEMVER:introduced=0,last_affected=0.3.1, SEMVER:introduced=0.0.0-0

## Identifiers

- CVE-2025-62518
- GHSA-j5gw-2vrg-8fgx
- RUSTSEC-2025-0110
- RUSTSEC-2025-0111

## Related threats

- [Astral astral-tokio-tar library unmaintained](https://junglewise.ai/threats/rustsec-2026-0440-astral-tokio-tar-is-unmaintained-9bf9b77f)
- [Astral astral-tokio-tar PAX header desynchronization](https://junglewise.ai/threats/astral-astral-tokio-tar-pax-header-desynchronization-c2fb9068)
- [RUSTSEC-2026-0145 - PAX Header Desynchronization in astral-tokio-tar](https://junglewise.ai/threats/rustsec-2026-0145-pax-header-desynchronization-in-astral-tokio-tar-01625d48)
- [astral-tokio-tar: `unpack_in` can chmod arbitrary directories by following symlinks](https://junglewise.ai/threats/astral-tokio-tar-unpack-in-can-chmod-arbitrary-directories-by-following-6d2f1c09)
- [astral-tokio-tar is Vulnerable to PAX Header Desynchronization](https://junglewise.ai/threats/astral-tokio-tar-is-vulnerable-to-pax-header-desynchronization-a46fcefa)