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.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| zammad | zammad | < 6.5.4, >= 7.0.0-alpha, < 7.0.1 | — |
Advisories 1
- WID-SEC-2026-1000 Zammad: Mehrere Schwachstellen BSI CERT-Bund (WID) · Apr 8, 2026