---
cve: "CVE-2026-34719"
severity: "HIGH"
cvss: 8.3
epss: "0.2%"
vendor: "Zammad"
kev: false
exploited: false
published: "2026-04-08 19:25:22"
tags: [cve, security, high]
source: tsecurity.de CVE-Dossier
exported: "2026-09-29T06:25:51+02:00"
---

# CVE-2026-34719

> 8.3 HIGH · 🧪 PoC

## Beschreibung

Zammad is a web based open source helpdesk/customer support system. Prior to 7.0.1 and 6.5.4, the webhook model was missing a proper validation for loop back addresses, or link-local addresses — only the URL scheme (HTTP/HTTPS) as well as the hostname was checked. This could end up in retrieving confidential metadata of cloud/hosting providers. The existing check is now extended and is applied when configuring webhooks as well as triggering webhook jobs. This vulnerability is fixed in 7.0.1 and 6.5.4.

## CISA-Anreicherung (vulnrichment/ADP)

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

## CVSS-Vektor

```
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:L/VI:N/VA:H/SC:L/SI:N/SA:H
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Netzwerk | bad |
| AC Komplexität | Gering | bad |
| PR Privilegien | Hoch | good |
| UI Interaktion | Keine | bad |

## Patch verfügbar (OSV)

- 15c7e6d4ffd95c84535d334b7c0ce0bc2fbc5228 (Commit)

## BSI-Hinweise (deutsch)

- [Zammad: Mehrere Schwachstellen](https://wid.cert-bund.de/portal/wid/sicherheitshinweis/WID-SEC-W-2026-1000)

## Referenzen

- <https://github.com/zammad/zammad/security/advisories/GHSA-2vgc-vfh2-rw75>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-34719) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI WID (CSAF)_