CVE-2026-84463

Zammad is a web based open source helpdesk/customer support system. Prior to 7.1.2, a user with Knowledge Base editing rights for a category can embed a video widget in a published answer with a specially crafted value. When the answer is rendered, that value is inserted into the page's HTML without being escaped for its attribute context, allowing it to break out and inject additional HTML into the page. When another user who has permission to switch between user sessions views the affected answer, the injected HTML causes their browser to silently send a request to Zammad's session-switching endpoint using their own active credentials. This results in switching their session to an account chosen by the person who wrote the Knowledge Base answer. No action is required from the viewer beyond opening the published answer. This issue is fixed in version 7.1.2.

CVSS

No CVSS.

References

Link	Resource
https://github.com/zammad/zammad/commit/f7a97ea209696bce85ed62901ee753b88368851c
https://github.com/zammad/zammad/security/advisories/GHSA-cxjg-4gmf-5xqc

Configurations

No configuration.

History

25 Sep 2026, 19:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-25 19:17

Updated : 2026-09-29 20:17

NVD link : CVE-2026-84463

Mitre link : CVE-2026-84463

CVE.ORG link : CVE-2026-84463

JSON object : View

Products Affected

No product.

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

CWE-352

Cross-Site Request Forgery (CSRF)

CWE-838

Inappropriate Encoding for Output Context

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