cve-2026-18508

MEDIUM CVSS 4.4 vulnrichment
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.

Timeline
Published
2026-08-03 14:51 UTC
Last Modified
2026-11-05
CVSS Details
Attack Vector
LOCAL
Attack Complexity
LOW
Privileges Required
NONE
Affected Products
  • Red Hat Red Hat Enterprise Linux 10
  • Red Hat Red Hat Enterprise Linux 8
  • Red Hat Red Hat Enterprise Linux 9
  • Red Hat Red Hat Discovery 2
  • Red Hat Red Hat Hardened Images
  • Red Hat Red Hat Update Infrastructure 5
  • Red Hat Red Hat Enterprise Linux 6
  • Red Hat Red Hat Enterprise Linux 7
  • Red Hat Red Hat OpenShift Container Platform 4
  • Red Hat Red Hat OpenShift Container Platform 5
Weaknesses (CWE)
CWE-59
SSVC (CISA Stakeholder-Specific Vulnerability Categorization) CISA Coordinator v2.0.3
Exploitation
none
Automatable
no
Technical Impact
partial
Decision timestamp
2026-08-03T16:02:27.313193Z

What is SSVC? — CISA's vulnerability-prioritisation framework using a decision tree rather than a single score.

References
Linked Vulnerabilities
elsa-2026-61581-0 oracle_linux
elsa-2026-61586-0 oracle_linux
elsa-2026-70390 oracle_linux
fedora-2026-044e56d9ff fedora
fedora-2026-ee1eb89e7b fedora
cpuoct2026csaf csaf_oracle 

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