---
cve: "CVE-2026-107218"
severity: "MEDIUM"
cvss: 5.3
epss: ""
vendor: "qax-os"
kev: false
exploited: false
published: "2026-10-07 19:17:34"
tags: [cve, security, medium]
source: tsecurity.de CVE-Dossier
exported: "2026-10-19T06:24:27+02:00"
---

# CVE-2026-107218

> 5.3 MEDIUM · 🧪 PoC

## Beschreibung

Excelize is a Go language library for reading and writing Microsoft Excel spreadsheets. From 2.10.1 to 2.11.0, RIGHT validates the requested length with UTF-16 code-unit counts but slices a rune array using Unicode code-point counts. RIGHT reaches leftRight through CalcCellValue, where countUTF16String validates one unit but utf8.RuneCountInString supplies the slice index in another. When RIGHT evaluates supplementary-plane text with a requested character count between the rune count and UTF-16 code-unit count, the inconsistent units produce a negative rune-slice index, allowing an attacker to panic during formula evaluation. No fixed version is available as of this review.

## CNA-Record (Kanon, cvelistV5)

- CNA: **GitHub_M**
- State: PUBLISHED
- Stand: 2026-10-07 22:05:36
- CNA-CVSS: **5.3** (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L`)

## CISA-Anreicherung (vulnrichment/ADP)

- CISA-SSVC (Coordinator, v2.0.3):
  - Exploitation: **none**
  - Automatable: **yes**
  - Technical Impact: **partial**

## CVSS-Vektor

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

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

## Schwachstellen-Klasse

- **CWE-129** — Improper Validation of Array Index
  The product uses untrusted input when calculating or using an array index, but the product does not validate or incorrectly validates the index to ensure the index references a valid position within the array.

## Angriffsmuster (CAPEC)

- [CAPEC-100 — Overflow Buffers](https://capec.mitre.org/data/definitions/100.html) _(Severity: Very High)_

## Patch verfügbar (OSV)

- ecd99d761fe0489f1ed308e2f7dc2e0502d1a396 (Commit)

## Referenzen

- <https://github.com/qax-os/excelize/security/advisories/GHSA-8jjq-8j9w-m2v6>
- <https://github.com/qax-os/excelize/pull/2390>
- <https://github.com/qax-os/excelize/commit/ecd99d761fe0489f1ed308e2f7dc2e0502d1a396>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/sicherheitsluecken/cve-2026-107218/) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI WID (CSAF)_