CVE-2026-33055

HIGH

tar-rs incorrectly ignores PAX size headers if header size is nonzero

Title source: cna
STIX 2.1

Description

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.

Scores

CVSS v3 8.1
EPSS 0.0001
EPSS Percentile 1.9%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N

CISA SSVC

Vulnrichment
Exploitation poc
Automatable yes
Technical Impact partial

Details

CWE
CWE-843
Status published
Products (2)
alexcrichton/tar-rs < 0.4.45 (2 CPE variants)
crates.io/tar 0 - 0.4.45crates.io
Published Mar 20, 2026
Tracked Since Mar 20, 2026