ZammadApplication

CVE-2021-42092

MEDIUM · 5.4 CVSS v3.1 Published 2021-10-07
Fix available
A fix is available. Upgrade to 4.1.1 or later.
See remediation →
58/100
Remediation priority · Elevated
Remotely reachable

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
An issue was discovered in Zammad before 4.1.1. Stored XSS may occur via an Article during addition of an attachment to a Ticket.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

Stored XSS vulnerability in Zammad before version 4.1.1 allows malicious script injection through the Article component when adding attachments to tickets. The application fails to properly sanitize attachment-related input, allowing persisted scripts to execute when other users view affected articles.

MitigationUpgrade Zammad to version 4.1.1 or later, which includes proper input sanitization for attachment handling in the Article module.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
ZammadApplication
Affected:< 4.1.1

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
Required
Scope
Changed
Confidentiality
Low
Integrity
Low
Availability
None

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Check Zammad version
    Locate the installed Zammad version through the admin interface (System > Info) or by querying the package manager/version file, then compare it against the vulnerable range (any version before 4.1.1)
    Affected if The installed version is below 4.1.1
  2. Verify Article module is in use
    Confirm that the Zammad installation actively uses the ticket system and that users can create or modify tickets with the Article component (the module handling ticket communications and attachments)
    Affected if The ticket system with Article functionality is enabled and accessible to users
  3. Inspect existing ticket articles for suspicious content
    Review ticket articles in the database or through the admin interface, specifically examining attachment metadata and content fields for injected script tags or encoded malicious payloads
    Affected if Any ticket articles contain unsanitized script tags, event handlers, or other XSS vectors in attachment-related fields
  4. Check recent audit logs for XSS indicators
    Review Zammad audit logs and user activity logs for patterns indicating exploitation attempts, such as unusual HTML/script injection in ticket fields or attachment descriptions
    Affected if Logs show patterns of script injection attempts in ticket or attachment fields

You are affected if your Zammad installation version is below 4.1.1 and the ticket system with Article attachments is in use, as the vulnerability allows stored XSS through unsanitized attachment input.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 4.1.1 or later
Fixed in 4.1.1
Interim mitigation

Upgrade Zammad to version 4.1.1 or later, which includes proper input sanitization for attachment handling in the Article module.

Recommended fix High confidence

4.1.1

  1. Upgrade Zammad to version 4.1.1 or later to resolve the stored XSS vulnerability in attachment handling

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Zammad Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing3.0 h
  • Review / QA2.0 h
11.0 hours of engineering $1,930
Get the upgrade done

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Scan for this in your stack

Free · runs locally
dbcve dependency scanner

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2021-42092 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data