CVE-2026-18508

MEDIUM

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

Title source: CVE List
STIX 2.1 vulnerability

Record summary

CVE-2026-18508 has a selected CVSS score of 4.4 (medium).

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.

Description source: CVE List

Exploitation context

CISA SSVC decision

ExploitationNone
AutomatableNo
Technical impactPartial

CISA Coordinator · SSVC 2.0.3 · Evaluated Aug 3, 2026 · Source: CVE List

Affected products and versions

Showing 12 of 17
ProductSourceVersion range

Red Hat Enterprise Linux 10

Browse Red Hat / Red Hat Enterprise Linux 10tar

Default status: affected

CVE ListVersion data not supplied

Red Hat Enterprise Linux 6

Browse Red Hat / Red Hat Enterprise Linux 6tar

Default status: unknown

CVE ListVersion data not supplied

Red Hat Enterprise Linux 7

Browse Red Hat / Red Hat Enterprise Linux 7tar

Default status: unknown

CVE ListVersion data not supplied

Red Hat Enterprise Linux 8

Browse Red Hat / Red Hat Enterprise Linux 8tar

Default status: affected

CVE ListVersion data not supplied

Red Hat Enterprise Linux 9

Browse Red Hat / Red Hat Enterprise Linux 9tar

Default status: affected

CVE ListVersion data not supplied

Red Hat Hardened Images

Browse Red Hat / Red Hat Hardened Imagesaardvark-dns

Default status: unaffected

CVE ListVersion data not supplied

Red Hat Hardened Images

Browse Red Hat / Red Hat Hardened Imageschunkah

Default status: unaffected

CVE ListVersion data not supplied

Red Hat Hardened Images

Browse Red Hat / Red Hat Hardened Imagesgrafana12.4

Default status: unaffected

CVE ListVersion data not supplied

Red Hat Hardened Images

Browse Red Hat / Red Hat Hardened Imagesgrafana13.1

Default status: unaffected

CVE ListVersion data not supplied

Red Hat Hardened Images

Browse Red Hat / Red Hat Hardened Imagesnetavark

Default status: unaffected

CVE ListVersion data not supplied

Red Hat Hardened Images

Browse Red Hat / Red Hat Hardened Imagesnodejs26

Default status: unaffected

CVE ListVersion data not supplied

Red Hat Hardened Images

Browse Red Hat / Red Hat Hardened Imagespython-cryptography

Default status: unaffected

CVE ListVersion data not supplied

References

4