CVE-2026-18508

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.

CVSS v3 4.4 MEDIUM

4.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 2.5

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/errata/RHSA-2026:50807	Vendor Advisory
https://access.redhat.com/errata/RHSA-2026:61581
https://access.redhat.com/errata/RHSA-2026:61586
https://access.redhat.com/errata/RHSA-2026:61783
https://access.redhat.com/errata/RHSA-2026:66018
https://access.redhat.com/errata/RHSA-2026:70390
https://access.redhat.com/security/cve/CVE-2026-18508	Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2509843	Issue Tracking Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:gnu:tar:1.35:::::::*
	cpe:2.3:a:redhat:openshift_container_platform:4.0:::::::*
	cpe:2.3:o:redhat:enterprise_linux:8.0:::::::*
	cpe:2.3:o:redhat:enterprise_linux:9.0:::::::*
	cpe:2.3:o:redhat:enterprise_linux:10.0:::::::*

History

22 Sep 2026, 22:17

Type	Values Removed	Values Added
References		() https://access.redhat.com/errata/RHSA-2026:70390 -

Information

Published : 2026-08-03 16:16

Updated : 2026-10-30 13:18

NVD link : CVE-2026-18508

Mitre link : CVE-2026-18508

CVE.ORG link : CVE-2026-18508

JSON object : View

Products Affected

redhat

openshift_container_platform
enterprise_linux

gnu

tar

CWE

CWE-59

Improper Link Resolution Before File Access ('Link Following')

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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."}], "lastModified": "2026-10-30T13:18:33.020", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:gnu:tar:1.35:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "753D60F2-E001-49F6-A9B7-D8FCDE7E26BD"}, {"criteria": "cpe:2.3:a:redhat:openshift_container_platform:4.0:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "932D137F-528B-4526-9A89-CD59FA1AB0FE"}, {"criteria": "cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "F4CFF558-3C47-480D-A2F0-BABF26042943"}, {"criteria": "cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "7F6FB57C-2BC7-487C-96DD-132683AEB35D"}, {"criteria": "cpe:2.3:o:redhat:enterprise_linux:10.0:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "D65C2163-CFC2-4ABB-8F4E-CB09CEBD006C"}], "operator": "OR"}]}], "sourceIdentifier": "secalert@redhat.com"}