# CVE-2026-18508: A flaw was found in GNU tar. When extracting an archive with the --one-top-level option, hardlink targets are not…

Source: https://junglewise.ai/threats/cve-2026-18508-a-flaw-was-found-in-gnu-tar-when-extracting-an-archive-with-the  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-03  
License: CC BY 4.0 with a link back

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.

Technologies: [Gnu Tar](https://junglewise.ai/threats/technologies/tar), [Redhat Enterprise Linux](https://junglewise.ai/threats/technologies/enterprise-linux), [Redhat Openshift Container Platform](https://junglewise.ai/threats/technologies/openshift-container-platform). Vendors: [Gnu](https://junglewise.ai/threats/vendors/gnu), [Redhat](https://junglewise.ai/threats/vendors/redhat).

## Quick answers

**Is CVE-2026-18508 exploited in the wild?** 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.

## Affected products

- Gnu Tar
- Redhat Enterprise Linux
- Redhat Openshift Container Platform

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