cve-2026-18477

MEDIUM CVSS 4.4 vulnrichment
Description

A TOCTOU (Time-of-Check Time-of-Use) vulnerability in GNU tar's incremental dumpdir 'X' rename handling allows a local attacker with write access to a directory being backed up to influence the restore process if the attacker has access to the system where the restore is being performed. During restoration, files or directories may be created, renamed or overwritten outside the intended extraction directory. This could lead to unauthorized file modification or, in some cases, privilege escalation. Exploitation does not require the attacker to modify or craft the archive, and standard backup and restore workflows—including extracting into a newly created directory without using the -P option do not mitigate the issue.

Timeline
Published
2026-08-03 15:34 UTC
Last Modified
2026-11-05
CVSS Details
Attack Vector
LOCAL
Attack Complexity
HIGH
Privileges Required
LOW
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-367
SSVC (CISA Stakeholder-Specific Vulnerability Categorization) CISA Coordinator v2.0.3
Exploitation
none
Automatable
no
Technical Impact
partial
Decision timestamp
2026-08-03T16:25:22.002230Z

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

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

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