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.
History

Wed, 08 Apr 2026 20:15:00 +0000

Type Values Removed Values Added
First Time appeared Zammad
Zammad zammad
Vendors & Products Zammad
Zammad zammad

Wed, 08 Apr 2026 18:45:00 +0000

Type Values Removed Values Added
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.
Title Zammad has a Server-side request forgery (SSRF) via webhooks
Weaknesses CWE-918
References
Metrics cvssV4_0

{'score': 8.3, 'vector': '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'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-04-08T18:02:16.224Z

Reserved: 2026-03-30T18:41:20.753Z

Link: CVE-2026-34719

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Awaiting Analysis

Published: 2026-04-08T19:25:22.003

Modified: 2026-04-08T21:26:13.410

Link: CVE-2026-34719

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-04-08T20:12:40Z