High severity · published Mar 20, 2026
CVE-2026-33055
tar-rs incorrectly ignores PAX size headers if header size is nonzero
8.1
CVSS
0.4%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 35% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
TA
tar-rs · alexcrichton
< 0.4.45 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-33055
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-33055
Patch
https://github.com/alexcrichton/tar-rs/commit/de1a5870e603758f430073688691165f21a33946
Exploit
https://github.com/alexcrichton/tar-rs/security/advisories/GHSA-gchp-q4r4-x4ff
Third Party Advisory
https://www.cve.org/CVERecord?id=CVE-2025-62518
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