[USN-8138-1] tar-rs vulnerability

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Ubuntu Security Notice USN-8138-1
April 01, 2026

rust-tar vulnerability
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A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 25.10
- Ubuntu 24.04 LTS
- Ubuntu 22.04 LTS

Summary:

tar-rs could be made to modify permissions on arbitrary directories.

Software Description:
- rust-tar: A tar archive reading/writing library for Rust

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 25.10
librust-tar-dev 0.4.43-4ubuntu0.1

Ubuntu 24.04 LTS
librust-tar-dev 0.4.40-1ubuntu0.1

Ubuntu 22.04 LTS
librust-tar+default-dev 0.4.37-3ubuntu0.1
librust-tar-dev 0.4.37-3ubuntu0.1

In general, a standard system update will make all the necessary changes.

References:
https://ubuntu.com/security/notices/USN-8138-1
CVE-2026-33056

Package Information:
https://launchpad.net/ubuntu/+source/rust-tar/0.4.43-4ubuntu0.1
https://launchpad.net/ubuntu/+source/rust-tar/0.4.40-1ubuntu0.1
https://launchpad.net/ubuntu/+source/rust-tar/0.4.37-3ubuntu0.1