PT-2026-26570 · Alexcrichton · Tar-Rs

Published 2026-03-20 · Updated 2026-03-20 · CVE-2026-33055

Mitre

CVSS v4.0

5.1

Medium

AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N

tar-rs is a tar archive reading/writing library for Rust. Versions 0.4.44 and below have conditional logic that skips the PAX size header in cases where the base header size is nonzero. As part of CVE-2025-62518, the astral-tokio-tar project was changed to correctly honor PAX size headers in the case where it was different from the base header. This is almost the inverse of the astral-tokio-tar issue. Any discrepancy in how tar parsers honor file size can be used to create archives that appear differently when unpacked by different archivers. In this case, the tar-rs (Rust tar) crate is an outlier in checking for the header size - other tar parsers (including e.g. Go archive/tar) unconditionally use the PAX size override. This can affect anything that uses the tar crate to parse archives and expects to have a consistent view with other parsers. This issue has been fixed in version 0.4.45.

Fix

Type Confusion

Weakness Enumeration

CWE-843

Related Identifiers

CVE-2026-33055

Affected Products

Tar-Rs

References · 4

• https://nvd.nist.gov/vuln/detail/CVE-2026-33055 · Security Note
• https://cve.org/CVERecord?id=CVE-2025-62518 · Security Note
• https://github.com/alexcrichton/tar-rs/security/advisories/GHSA-gchp-q4r4-x4ff · Note
• https://github.com/alexcrichton/tar-rs/commit/de1a5870e603758f430073688691165f21a33946 · Note