Zammad: Stored HTML injection in Knowledge Base video widget enables forced session switching via unescaped iframe attribute (CVE-2026-84463) | HOL Guard CVE

Medium · CVSS 6.3CVE-2026-84463

Zammad: Stored HTML injection in Knowledge Base video widget enables forced session switching via unescaped iframe attribute

Answer in brief

CVE-2026-84463 records a Medium severity (CVSS 6.3) vulnerability in Zammad: Stored HTML injection in Knowledge Base video widget enables forced session switching via unescaped iframe attribute. The current sources do not mark it as known exploited. The current feed maps zammad/zammad (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 25, 2026Updated Sep 25, 2026Source checked Sep 25, 2026First seen by HOL Sep 25, 2026Material review Sep 25, 2026

Upstream Advisory

Key facts

Risk: Medium · CVSS 6.3
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Available

Why this deserves its current priority

CVSS is 6.3. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps zammad/zammad (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
zammad/zammadgeneric	<7.1.2	7.1.2

Recommended response

Check inventory. Check lockfiles and deployed manifests for zammad/zammad.
Review the reported fix. Update zammad/zammad to 7.1.2 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Sep 25, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 25, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 25, 2026

Sources and claim methodology

Upstream source description

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.

Quoted source text, attributed separately from HOL analysis.