---
cve: "CVE-2026-18508"
severity: "MEDIUM"
cvss: 4.4
epss: "0.1%"
vendor: "Red Hat"
kev: false
exploited: false
published: "2026-08-03 16:16:28"
tags: [cve, security, medium]
source: tsecurity.de CVE-Dossier
exported: "2026-09-28T03:59:24+02:00"
---

# CVE-2026-18508

> 4.4 MEDIUM

## Beschreibung

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.

## CISA-Anreicherung (vulnrichment/ADP)

- CISA-SSVC (Coordinator, v2.0.3):
  - Exploitation: **none**
  - Automatable: **no**
  - Technical Impact: **partial**

## CVSS-Vektor

```
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Lokal | good |
| AC Komplexität | Gering | bad |
| PR Privilegien | Keine | bad |
| UI Interaktion | Erforderlich | good |
| S Scope | Unverändert | good |
| C Vertraulichkeit | Gering | warn |
| I Integrität | Gering | warn |
| A Verfügbarkeit | Keine | good |

## BSI-Hinweise (deutsch)

- [GNU tar: Mehrere Schwachstellen ermöglichen Manipulation von Dateien](https://wid.cert-bund.de/portal/wid/sicherheitshinweis/WID-SEC-W-2026-2633) — _BSI-Einstufung: mittel_
  Ein Angreifer kann mehrere Schwachstellen in GNU tar ausnutzen, um Dateien zu manipulieren.

## Referenzen

- <https://access.redhat.com/errata/RHSA-2026:50807>
- <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-2026-18508>
- <https://bugzilla.redhat.com/show_bug.cgi?id=2509843>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-18508) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI WID (CSAF)_