CVE-2026-34719

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.

CVSS v3 4.3 MEDIUM

4.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/zammad/zammad/security/advisories/GHSA-2vgc-vfh2-rw75	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:zammad:zammad::::::::
	cpe:2.3:a:zammad:zammad:7.0.0:::::::*

History

No history.

Information

Published : 2026-04-08 19:25

Updated : 2026-07-24 22:10

NVD link : CVE-2026-34719

Mitre link : CVE-2026-34719

CVE.ORG link : CVE-2026-34719

JSON object : View

Products Affected

zammad

zammad

CWE

CWE-918

Server-Side Request Forgery (SSRF)

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La verificaci\u00f3n existente ahora se ha extendido y se aplica al configurar webhooks as\u00ed como al activar trabajos de webhook. Esta vulnerabilidad se ha corregido en 7.0.1 y 6.5.4."}], "lastModified": "2026-07-24T22:10:00.140", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:zammad:zammad:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "5AC4AB35-4DD1-43F8-B481-27640E70CF8A", "versionEndExcluding": "6.5.4"}, {"criteria": "cpe:2.3:a:zammad:zammad:7.0.0:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "830AF7C5-9441-4C80-935E-C53BDB097BB1"}], "operator": "OR"}]}], "sourceIdentifier": "security-advisories@github.com"}