CVE-2026-18508

Severity CVSS v4.0:

Pending analysis

Type:

CWE-59 Link Following

Publication date:

03/08/2026

Last modified:

07/08/2026

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.

Impact

Vector 3.x

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N CVSS v3.1 Severity and Metrics:

Base Score: 4.40 MEDIUM
Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N

Attack Vector (AV): Local
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): Required
Scope (S): Unchanged
Confidentiality (C): Low
Integrity (I): Low
Availability (A): None

Base Score 3.x

4.40

Severity 3.x

MEDIUM

CVE-2026-18508

Description

Impact

References to Advisories, Solutions, and Tools