CVE-2026-34720

Zammad is a web based open source helpdesk/customer support system. Prior to 7.0.1 and 6.5.4, the SSO mechanism in Zammad was not verifying the header originates from a trusted SSO proxy/gateway before applying further actions on it. 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-hcv6-w4h9-p2p7	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-2026-34720

Mitre link : CVE-2026-34720

CVE.ORG link : CVE-2026-34720

JSON object : View

Products Affected

zammad

zammad

CWE

CWE-346

Origin Validation Error

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