CVE-2026-34719

MEDIUM

Zammad has a Server-side request forgery (SSRF) via webhooks

Title source: cna

Description

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.

References (1)

[X_Refsource_Confirm] https://github.com/zammad/zammad/security/advisories/GHSA-2vgc-vfh2-rw75

Scores

CVSS v3 4.3

EPSS 0.0003

EPSS Percentile 7.5%

Attack Vector NETWORK

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

CISA SSVC

Vulnrichment

Exploitation none

Automatable no

Technical Impact partial

Details

CWE

CWE-918

Status published

Products (3)

zammad/zammad 7.0.0

zammad/zammad < 6.5.4 (2 CPE variants)

zammad/zammad >= 7.0.0-alpha, < 7.0.1

Published Apr 08, 2026

Tracked Since Apr 09, 2026