# CVE-2026-5223: Rust Cargo symlink traversal in crate extraction

Source: https://junglewise.ai/threats/cve-2026-5223-rust-cargo-symlink-traversal-in-crate-extraction  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-05-25. Updated: 2026-06-26  
License: CC BY 4.0 with a link back

CVE-2026-5223 · Severity: medium · CVSS 4 · Published 2026-05-25

Cargo, the package manager for the Rust programming language, contains a vulnerability that affects users of third-party software registries. A malicious software package could be crafted to overwrite the source code of other packages stored in a developer's local cache. This could lead to the silent inclusion of malicious code in future software builds, potentially compromising the integrity of applications and development environments.

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

## Quick answers

**Is CVE-2026-5223 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-5223 being exploited in the wild.

**How severe is CVE-2026-5223?** Medium severity, with a CVSS score of 4, published 25 May 2026.

**Which products and versions are affected?** cargo (crates.io) SEMVER:introduced=0,fixed=0.97.0; Rust Foundation Cargo < 0.97.0 (Rust < 1.96.0), All versions before Rust 1.96.0.

**Is there a fix for CVE-2026-5223?** Yes. cargo (crates.io): upgrade to 0.97.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-5223 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-5223?** Check whether you run cargo (crates.io) or Rust Foundation Cargo 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

- cargo (crates.io): upgrade to 0.97.0 or later

  ```sh
  cargo update -p cargo
  ```


## Technical details

A vulnerability exists in Cargo's crate extraction logic where symbolic links (symlinks) within crate tarballs are not properly restricted. While Cargo has protections to prevent extraction outside the crate's cache directory, a crafted tarball can extract files one level below its own directory. This allows an attacker to overwrite the source code of other crates belonging to the same third-party registry within the local `~/.cargo` cache. The attack requires a user to download a malicious crate from a non-crates.io registry (as crates.io already blocks symlinks). The issue is resolved in Cargo version 0.97.0 (shipped with Rust 1.96.0) by rejecting all symlinks during extraction.

## Affected products

- Rust Cargo < 0.97.0 (Rust < 1.96.0)

## Identifiers

- CVE-2026-5223
- GHSA-jq42-7mfv-hm57

## Timeline

- 2026-05-25: advisory: Initial advisory and NVD publication
- 2026-05-28: patched: Rust 1.96.0 released with the fix
- 2026-06-26: other: GitHub Advisory Database entry updated

## References

- [https://api.github.com/users/christos-spearbit](https://api.github.com/users/christos-spearbit)
- [https://github.com/christos-spearbit](https://github.com/christos-spearbit)
- [https://api.github.com/users/christos-spearbit/gists%7B/gist_id%7D](https://api.github.com/users/christos-spearbit/gists%7B/gist_id%7D)
- [https://api.github.com/users/christos-spearbit/repos](https://api.github.com/users/christos-spearbit/repos)
- [https://avatars.githubusercontent.com/u/265288016?v=4](https://avatars.githubusercontent.com/u/265288016?v=4)
- [https://api.github.com/users/christos-spearbit/events%7B/privacy%7D](https://api.github.com/users/christos-spearbit/events%7B/privacy%7D)

## Related threats

- [Rust Cargo credential leakage via incorrect URL normalization in sparse registries](https://junglewise.ai/threats/cve-2026-5222-rust-cargo-credential-leakage-via-incorrect-url-normalization-in)
- [Malicious dependencies can inject arbitrary JavaScript into cargo-generated timing reports](https://junglewise.ai/threats/cve-2023-40030-malicious-dependencies-can-inject-arbitrary-javascript-into-cargo)
- [Cargo not respecting umask when extracting crate archives](https://junglewise.ai/threats/cve-2023-38497-cargo-not-respecting-umask-when-extracting-crate-archives)
- [Cargo did not verify SSH host keys](https://junglewise.ai/threats/cve-2022-46176-cargo-did-not-verify-ssh-host-keys)
- [Cargo extracting malicious crates can corrupt arbitrary files](https://junglewise.ai/threats/cve-2022-36113-cargo-extracting-malicious-crates-can-corrupt-arbitrary-files)