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CVE-2026-18508

Tar: tar: --one-top-level hardlink targets not confined to top-level directory enabling arbitrary file overwrite

Published: Aug 3, 2026Updated: Aug 7, 2026 Sources: CVE List NVDCWE-59
4.4MEDIUM
NVD MITRE
EPSS Score
0.1%
Top 96.4%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Workaround Only
Self-Check
Not available

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.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:LAC:LPR:NUI:RS:UC:LI:LA:N
Exploitability
AV:LAttack Vector
Local
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:RUser Interaction
Required
Scope
S:UScope
Unchanged
Impact
C:LConfidentiality
Low
I:LIntegrity
Low
A:NAvailability
None
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Weaknesses

CWE-59

Affected Products

Red Hat
commercial·US
Red Hat Hardened ImagesOn-premOS
Operating Systems / linux-distro
Red Hat Enterprise Linux 10On-premOS
Operating Systems / linux-distro
Red Hat OpenShift Container Platform 4SaaSSaaS Service
Cloud & SaaS / container-orchestration
and 4 more affected products View all →

Exploitability

Workaround Available

Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

2 techniques
Collection
Discovery
View detailed technique mapping

References

https://access.redhat.com/errata/RHSA-2026:50807
access.redhat.com
https://access.redhat.com/security/cve/CVE-2026-18508
access.redhat.com
https://bugzilla.redhat.com/show_bug.cgi?id=2509843
bugzilla.redhat.com

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