Description
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; redhat: openshift container platform; redhat: enterprise linux
References8
- access.redhat.com/errata/RHSA-2026:50807 Vendor Advisory
- access.redhat.com/security/cve/CVE-2026-18508 Vendor Advisory
- bugzilla.redhat.com/show_bug.cgi?id=2509843 Issue TrackingVendor Advisory
- access.redhat.com/errata/RHSA-2026:61581
- access.redhat.com/errata/RHSA-2026:61586
- access.redhat.com/errata/RHSA-2026:61783
- access.redhat.com/errata/RHSA-2026:66018
- access.redhat.com/errata/RHSA-2026:70390
Metrics
- CVSS 3.1
-
4.4
MEDIUM
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N - EPSS — exploit probability
- 0% percentile: 3 · as of 13 November 2026
- CWE
- CWE-59
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