Zammad: Stored HTML injection in Knowledge Base video widget enables forced session switching via unescaped iframe attribute
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.
CVE-2026-84463
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-84463
zammad
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"vendor": "zammad",
"product": "zammad",
"versions": [
{
"status": "affected",
"version": "< 7.1.2"
}
]
}
]- Related CVEs
- CVE-2026-84463
Source reference:
/cveMetadata/cveId
Publisher severity
medium
Source reference: /containers/cna/metrics
- Event
- #3993 · Revision 1
- Added to Heist Feed
- Publisher date