CVE-2026-18508: GNU Tar

Medium severity, CVSS 4.4. EPSS: 0.1% chance of exploitation in the next 30 days.

A flaw was found in GNU tar. When extracting an archive with the --one-top-level option, hardlink targets are not confined to the designated top-level directory and may resolve relative to the extraction working directory. A crafted archive can create hardlinks that escape the intended boundary and, when combined with a preexisting symbolic link under the working directory, may allow writing outside that boundary during a single extraction.

Affected products

• GNU Tar: version 1.35 only
• Red Hat Enterprise Linux: version 8.0 only; version 9.0 only; version 10.0 only
• Red Hat Openshift Container Platform: version 4.0 only

Published 2026-08-03. Last modified 2026-09-22.