CVE-2021-42085
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 · uneditedAn issue was discovered in Zammad before 4.1.1. There is stored XSS via a custom Avatar.
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 confidenceZammad before version 4.1.1 contains a stored Cross-Site Scripting (XSS) vulnerability in the custom Avatar upload functionality. Attackers can inject malicious JavaScript code through avatar image uploads that executes when other users view the avatar.
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< 4.1.1CVSS 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 checksWork through these to decide whether this CVE applies to you.
-
Confirm Zammad installationCheck if Zammad is installed on the system by looking for its installation directory (typically /opt/zammad) or by running: which zammad, rpm -q zammad, or dpkg -l | grep zammadAffected if Zammad is not installed on the system
-
Determine installed Zammad versionRun the Zammad version command: zammad --version or check the web interface (usually at /about in the admin panel) or inspect the installed package: rpm -q --qf '%{VERSION}' zammad or dpkg -s zammad 2>/dev/null | grep VersionAffected if The installed version is lower than 4.1.1 (e.g., 4.0.x, 3.x, etc.)
-
Verify custom avatar upload is accessibleLog into Zammad as a regular user, navigate to User Profile or Settings area, and check if an option to upload a custom avatar image exists (typically under Profile > Avatar or similar)Affected if The custom avatar upload feature is available and users can upload image files
-
Check user permissions for avatar uploadIn the Zammad admin panel (Admin > Users), verify if regular users have permission to change their profile avatar or if the setting 'user_can_upload_avatar' is enabled in the system configurationAffected if Regular (non-admin) users have permission to upload custom avatars
You are affected if Zammad is installed with a version lower than 4.1.1 and the custom avatar upload feature is accessible to users in your environment.
Generated from the published advisory. Verify against your own configuration.
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 · scoped4.1.1
Upgrade Zammad to version 4.1.1 or later to patch the stored XSS vulnerability in the avatar upload feature.
Zammad 4.1.1
- Upgrade Zammad to version 4.1.1 or later to remediate the stored XSS vulnerability via custom Avatar
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation1.0 h
- Implementation2.0 h
- Testing2.0 h
- Review / QA1.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,664.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-42085 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2021-42085 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.
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.
- 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