CVE-2026-34718
Medium
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.
SeverityMedium
CVSS6.1
Exploit probability—
Product
Zammad
PublishedApr 8, 2026
First seenApr 8, 2026
Weakness typeCWE-80CWE-80
How to fix
Update
- zammad zammad6.5.4 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| zammad zammad | v < 6.5.4, 7.0.0 | 6.5.4 |
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