---
cve: "CVE-2023-28999"
severity: "MEDIUM"
cvss: 6.9
epss: "68%"
vendor: "nextcloud"
kev: false
exploited: false
published: "2023-04-04 13:15:09"
tags: [cve, security, medium]
source: tsecurity.de CVE-Dossier
exported: "2026-09-11T13:03:45+02:00"
---

# CVE-2023-28999

> 6.9 MEDIUM · 🧪 PoC

## Beschreibung

Nextcloud is an open-source productivity platform. In Nextcloud Desktop client 3.0.0 until 3.8.0, Nextcloud Android app 3.13.0 until 3.25.0, and Nextcloud iOS app 3.0.5 until 4.8.0, a malicious server administrator can gain full access to an end-to-end encrypted folder. They can decrypt files, recover the folder structure and add new files.​ This issue is fixed in Nextcloud Desktop 3.8.0, Nextcloud Android 3.25.0, and Nextcloud iOS 4.8.0. No known workarounds are available.

## CVSS-Vektor

```
CVSS:3.1/AV:P/AC:L/PR:H/UI:R/S:C/C:H/I:H/A:L
```

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

## Patch verfügbar (OSV)

- 729ff137b27c49ebe1e9fcb74f420cc625d1084c (Commit)
- b15f9376b2761b7dd9726aa3a110b1077ef57094 (Commit)

## Referenzen

- <https://github.com/nextcloud/security-advisories/security/advisories/GHSA-8875-wxww-3rr8>
- <https://github.com/nextcloud/desktop/pull/5560>
- <https://ethz.ch/content/dam/ethz/special-interest/infk/inst-infsec/appliedcrypto/education/theses/report_DanieleCoppola.pdf>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2023-28999) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_