astral-tokio-tar Vulnerable to PAX Header Desynchronization
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- Required
- Attack complexity
- Low
- Impact type
- Code execution
- Confidentiality · integrity · availability
- High · High · None
- Fix status
- Partial Red Hat: 2 without a fix
Attack profile from CVSS 3.1 · CNA. Fix status from CNA, GitHub and Red Hat. Impact type from CWE-843 and the CVSS impact.
Summary
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.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- No
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| astral-sh | tokio-tar | before 0.5.6 | 0.5.6 | Patch available | CNA |
| — | astral-tokio-tar (crates.io) | before 0.5.6 | 0.5.6 | Patch available | GHSA-j5gw-2vrg-8fgx |
| — | tokio-tar (crates.io) | up to 0.3.1 | — | No fix listed | GHSA-j5gw-2vrg-8fgx |
- tokio-tar Vendorastral-sh Affected before 0.5.6 Fixed in 0.5.6 Patch available CNA
- astral-tokio-tar (crates.io) Vendor— Affected before 0.5.6 Fixed in 0.5.6 Patch available GHSA-j5gw-2vrg-8fgx
- tokio-tar (crates.io) Vendor— Affected up to 0.3.1 Fixed in — No fix listed GHSA-j5gw-2vrg-8fgx
Remediation
- Fix · CNA tokio-tar (astral-sh) Fixed in 0.5.6
- Fix · GHSA-j5gw-2vrg-8fgx astral-tokio-tar (crates.io) Fixed in 0.5.6 Advisory →
Vendor assessments
Red Hat
Red Hat rating: Important. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Confidential Compute Attestation | Affected | No fix yet |
| Red Hat OpenShift Container Platform 4 | Affected | No fix planned: Will not fix |
Not affected: 3 products
- Confidential Compute Attestation
- Red Hat Enterprise Linux 10
- Red Hat Enterprise Linux 9
Timeline
- 2026-10-02 Threatist record created from CVE-2025-62518
- 2026-10-03 Alias added: GHSA-j5gw-2vrg-8fgx
References
Other 8
- https://github.com/astral-sh/tokio-tar/security/advisories/GHSA-j5gw-2vrg-8fgx
- https://github.com/astral-sh/uv/security/advisories/GHSA-w476-p2h3-79g9
- https://github.com/astral-sh/tokio-tar/commit/22b3f884adb7a2adf1d3a8d03469533f5cbc8318
- https://edera.dev/stories/tarmageddon
- https://github.com/edera-dev/cve-tarmageddon
- https://github.com/astral-sh/tokio-tar
- https://rustsec.org/advisories/RUSTSEC-2025-0110.html
- https://rustsec.org/advisories/RUSTSEC-2025-0111.html
More astral-sh vulnerabilities
- TI-2026-78723 Path traversal in Astral uv lets attackers delete arbitrary files CVSS 4.0HIGH 8.7
- TI-2025-43946 Path traversal in Astral uv sdist extraction allows file writes CVSS 4.0HIGH 8.7
- TI-2026-78722 Path traversal in uv lets malicious wheels write files CVSS 4.0HIGH 8.7
- TI-2025-34180 uv is vulnerable to ZIP payload obfuscation through parsing differentials CVSS 4.0MEDIUM 6.8
- TI-2026-66129 uv: Path traversal on Windows through wheel extraction CVSS 4.0MEDIUM 5.9
- TI-2025-37264 astral-tokio-tar has a path traversal in tar extraction CVSS 4.0MEDIUM 6.1
Sources
- CVE-2025-62518 · CVE Program
- CVE-2025-62518 · NVD
- FIRST EPSS
- GHSA-j5gw-2vrg-8fgx · GitHub Advisory Database · CC BY 4.0
- CVE-2025-62518 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences