CVE-2026-34718

Zammad improperly neutralizes of script-related HTML tags in ticket articles

State: Published
Severity: 5.3 Medium
Published: Apr 8, 2026
Updated: Apr 8, 2026
Reserved: Mar 30, 2026

Description

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.

Scores

CVSS	Score	Vector	Source
4.0	5.3 Medium	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N	GitHub_M

Weaknesses

CWE-80 Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS)

Affected Products

Product	Versions
zammadzammad	< 6.5.4Affected >= 7.0.0-alpha, < 7.0.1Affected

References

https://github.com/zammad/zammad/security/advisories/GHSA-c2cf-9fc7-jhf3

Every record here comes from the CVE Program’s CVE List. © 1999–2026 The MITRE Corporation. CVE is a registered trademark of The MITRE Corporation. The records are reproduced under the CVE Program terms of use.