---
cve: "CVE-2026-35539"
severity: "MEDIUM"
cvss: 6.1
epss: "25%"
vendor: "Roundcube"
kev: false
exploited: false
published: "2026-04-03 03:39:17"
tags: [cve, security, medium]
source: tsecurity.de CVE-Dossier
exported: "2026-09-03T04:56:27+02:00"
---

# CVE-2026-35539

> 6.1 MEDIUM · 🧪 PoC

## Beschreibung

An issue was discovered in Roundcube Webmail before 1.5.14 and 1.6.14. XSS exists because of insufficient HTML attachment sanitization in preview mode. A victim must preview a text/html attachment.

## CVSS-Vektor

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

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

## Patch verfügbar (OSV)

- d742954ccbcdee7020f8f2e7c49ce0fca5a0efab (Commit)
- 27ec6cc9cb25e1ef8b4d4ef39ce76d619caa6870 (Commit)

## Referenzen

- <https://roundcube.net/news/2026/03/18/security-updates-1.7-rc5-1.6.14-1.5.14>
- <https://github.com/roundcube/roundcubemail/releases/tag/1.7-rc5>
- <https://github.com/roundcube/roundcubemail/commit/1b30edf5369668c92fe91dae3d52e477c808aa4f>
- <https://github.com/roundcube/roundcubemail/releases/tag/1.6.14>
- <https://github.com/roundcube/roundcubemail/commit/10a6d1fa8acac85c727b0a6ae4a6642bfa27bea1>
- <https://github.com/roundcube/roundcubemail/releases/tag/1.5.14>
- <https://github.com/roundcube/roundcubemail/commit/d742954ccbcdee7020f8f2e7c49ce0fca5a0efab>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-35539) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_