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

17 Apr 2026, 15:25

Type	Values Removed	Values Added
CPE		cpe:2.3:a:zammad:zammad:7.0.0:::::::* cpe:2.3:a:zammad:zammad::::::::
First Time		Zammad zammad Zammad
References	~~() https://github.com/zammad/zammad/security/advisories/GHSA-hcv6-w4h9-p2p7 -~~	() https://github.com/zammad/zammad/security/advisories/GHSA-hcv6-w4h9-p2p7 - Vendor Advisory
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 4.3

08 Apr 2026, 19:25

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-04-08 19:25

Updated : 2026-04-17 15:25

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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