CVE-2026-33056 MEDIUM

CVE-2026-33056: tar-rs: unpack_in can chmod arbitrary directories by following symlinks

Vendor Alexcrichton
Product tar-rs
Weakness CWE-61
Published March 20, 2026
Last update March 20, 2026

CVSS base score

5.1/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction
Confidentiality
Integrity

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N

What the vulnerability does

01Description

tar-rs is a tar archive reading/writing library for Rust. In versions 0.4.44 and below, when unpacking a tar archive, the tar crate's unpack_dir function uses fs::metadata() to check whether a path that already exists is a directory. Because fs::metadata() follows symbolic links, a crafted tarball containing a symlink entry followed by a directory entry with the same name causes the crate to treat the symlink target as a valid existing directory — and subsequently apply chmod to it. This allows an attacker to modify the permissions of arbitrary directories outside the extraction root. This issue has been fixed in version 0.4.45.

Key dates

02Disclosure timeline

March 20, 2026 CVE published
March 20, 2026 Record updated