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.
Affected products
gnu: tar; redhat: openshift container platform; redhat: enterprise linux
References8
- access.redhat.com/errata/RHSA-2026:49361 Vendor Advisory
- access.redhat.com/security/cve/CVE-2026-18477 Vendor Advisory
- bugzilla.redhat.com/show_bug.cgi?id=2509735 Issue TrackingVendor Advisory
- access.redhat.com/errata/RHSA-2026:61581
- access.redhat.com/errata/RHSA-2026:61586
- access.redhat.com/errata/RHSA-2026:61783
- access.redhat.com/errata/RHSA-2026:66018
- access.redhat.com/errata/RHSA-2026:70390
Metrics
- CVSS 3.1
-
4.4
MEDIUM
Score source: CNA
CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:N/I:H/A:N - EPSS — exploit probability
- 0% percentile: 1 · as of 13 November 2026
- CWE
- CWE-367
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