CVE-2026-18508: A flaw was found in GNU tar. When extracting an archive with the --one-top-level option, hardlink targets are not…
CVE-2026-18508 · Severity: medium · CVSS 4.4 · Published 2026-08-03
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.
No. Junglewise Threat Intelligence has no report of CVE-2026-18508 being exploited in the wild.
How severe is CVE-2026-18508?
Medium severity, with a CVSS score of 4.4, published 3 August 2026.
Which products and versions are affected?
Gnu Tar, Redhat Enterprise Linux, Redhat Openshift Container Platform. The advisory does not name versions.
Is there a fix for CVE-2026-18508?
No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
Am I affected by CVE-2026-18508?
Check whether you run Gnu Tar, Redhat Enterprise Linux or Redhat Openshift Container Platform. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.