CVE-2026-18508

MEDIUM

GNU tar --one-top-level - Hardlink Arbitrary File Overwrite

Title source: manual
STIX 2.1

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.

References (3)

Core 3
Core References
Vdb Entry, X_Refsource_Redhat vdb-entry x_refsource_redhat
https://access.redhat.com/security/cve/CVE-2026-18508
Issue Tracking, X_Refsource_Redhat issue-tracking x_refsource_redhat
RHBZ#2509843
https://bugzilla.redhat.com/show_bug.cgi?id=2509843
Vendor Advisory vendor-advisory x_refsource_redhat
RHSA-2026:50807
https://access.redhat.com/errata/RHSA-2026:50807

Scores

CVSS v3 4.4
EPSS 0.0013
EPSS Percentile 3.1%
Attack Vector LOCAL
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-59
Status published
Products (8)
Red Hat/Red Hat Enterprise Linux 10
Red Hat/Red Hat Enterprise Linux 6
Red Hat/Red Hat Enterprise Linux 7
Red Hat/Red Hat Enterprise Linux 8
Red Hat/Red Hat Enterprise Linux 9
Red Hat/Red Hat Hardened Images
Red Hat/Red Hat Hardened Images 1.35-9.2.hum1
Red Hat/Red Hat OpenShift Container Platform 4
Published Aug 03, 2026
Tracked Since Aug 03, 2026