ESB-2026.3675
PUBLISHED
CVSS 6.5 MEDIUM
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AUSCERT External Security Bulletin Redistribution
ESB-2026.3675
USN-8138-2: tar-rs vulnerability
15 April 2026
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AUSCERT Security Bulletin Summary
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Product: tar-rs
Publisher: Ubuntu
Operating System: Ubuntu
Resolution: Patch/Upgrade
CVE Names: CVE-2026-33056
Original Bulletin:
https://ubuntu.com/security/notices/USN-8138-2
Comment: CVSS (Max): 6.5 CVE-2026-33056 (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N)
CVSS Source: NIST
Calculator: https://www.first.org/cvss/calculator/3.1#CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
EPSS (Max): 0.0% (1st) CVE-2026-33056 2026-04-14
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USN-8138-2: tar-rs vulnerability
Publication date
14 April 2026
Overview
tar-rs could be made to modify permissions on arbitrary directories.
Releases
20.04 LTS
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Open side navigation
Packages
o rust-tar - A tar archive reading/writing library for Rust
Details
USN-8138-1 fixed a vulnerability in tar-rs. This update provides the
corresponding update for Ubuntu 20.04 LTS.
Original advisory details:
It was discovered that tar-rs incorrectly handled symlinks when unpacking
a tar archive. If a user or automated system were tricked into processing
a specially crafted tar archive, a remote attacker could use this issue to
modify permissions of arbitrary directories outside the extraction root,
and possibly escalate privileges.
Update instructions
The problem can be corrected by updating your system to the following package
versions:
Ubuntu Package Version
Release
20.04 LTS librust-tar-dev - 0.4.26-1ubuntu0.1 Ubuntu Pro Fix available with
focal Ubuntu Pro .
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References
o CVE-2026-33056
Related notices
o USN-8168-1
o USN-8168-2
o USN-8139-1
o USN-8138-1
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