---
cve: "CVE-2021-26564"
severity: "HIGH"
cvss: 8.3
epss: "0.7%"
vendor: "Synology"
kev: false
exploited: false
published: "2021-02-26 21:45:33"
tags: [cve, security, high]
source: tsecurity.de CVE-Dossier
exported: "2026-10-01T13:49:30+02:00"
---

# CVE-2021-26564

> 8.3 HIGH

## Beschreibung

Cleartext transmission of sensitive information vulnerability in synorelayd in Synology DiskStation Manager (DSM) before 6.2.3-25426-3 allows man-in-the-middle attackers to spoof servers via an HTTP session.

## CVSS-Vektor

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

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

## Referenzen

- <https://www.synology.com/security/advisory/Synology_SA_20_26>
- <https://www.talosintelligence.com/vulnerability_reports/TALOS-2020-1160>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2021-26564) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI WID (CSAF)_