CVE-2026-34718

Zammad is a web based open source helpdesk/customer support system. Prior to 7.0.1 and 6.5.4, the HTML sanitizer for ticket articles was missing proper sanitization of data: ... URI schemes, resulting in storing such malicious content in the database of the Zammad instance. The Zammad GUI is rendering this content, due to applied CSP rules no harm was done by e.g., clicking such a link. This vulnerability is fixed in 7.0.1 and 6.5.4.

CVSS v3 6.1 MEDIUM

6.1^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/zammad/zammad/security/advisories/GHSA-c2cf-9fc7-jhf3	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, 15:39

Type	Values Removed	Values Added
References	~~() https://github.com/zammad/zammad/security/advisories/GHSA-c2cf-9fc7-jhf3 -~~	() https://github.com/zammad/zammad/security/advisories/GHSA-c2cf-9fc7-jhf3 - Vendor Advisory
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 6.1
CPE		cpe:2.3:a:zammad:zammad:7.0.0:::::::* cpe:2.3:a:zammad:zammad::::::::
First Time		Zammad zammad Zammad

08 Apr 2026, 19:25

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-04-08 19:25

Updated : 2026-04-17 15:39

NVD link : CVE-2026-34718

Mitre link : CVE-2026-34718

CVE.ORG link : CVE-2026-34718

JSON object : View

Products Affected

zammad

zammad

CWE

CWE-80

Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS)

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