CVE-2026-34719 — Zammad has a Server-side request forgery (SSRF) via webhooks
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-…
Published: 2026-04-08 · CVSS: 8.3 · CVSS 4.0
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.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7