CVE-2026-18477
Estado: ModificadaMedia (4.4)—
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.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:N/I:H/A:N
- Puntuación base: 4.4
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.08%
- Percentil entre todas las CVEs puntuadas: 0
- Fecha de la puntuación: 5/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
Tecnologías afectadas (3)
CWE
- CWE-367
Referencias
- https://access.redhat.com/errata/RHSA-2026:49361
- https://access.redhat.com/errata/RHSA-2026:61581
- https://access.redhat.com/errata/RHSA-2026:61586
- https://access.redhat.com/errata/RHSA-2026:61783
- https://access.redhat.com/errata/RHSA-2026:66018
- https://access.redhat.com/errata/RHSA-2026:70390
- https://access.redhat.com/security/cve/CVE-2026-18477
- https://bugzilla.redhat.com/show_bug.cgi?id=2509735
JSON original (NVD)
Mostrar
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