CVE-2021-42093
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. An admin can execute code on the server via a crafted request that manipulates triggers.
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 confidenceAuthenticated admin users can achieve remote code execution on the Zammad server by submitting crafted requests that manipulate triggers. The vulnerability exists in Zammad versions prior to 4.1.1 and allows privilege escalation from admin to system-level code execution.
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
- High
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
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.
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Identify installed Zammad versionAccess the admin interface (typically /#admin) and navigate to System > Information, or run the command: zammad run rails r "puts Setting.get('product_version')"Affected if The version displayed is lower than 4.1.1 (e.g., 4.0.0, 3.x, etc.)
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Verify admin access existsConfirm that at least one user account with admin privileges exists in the system. Check via Users panel in the admin interface.Affected if Any admin user account is present in the system
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Check for trigger configurationsNavigate to the Triggers section in the admin panel (typically under Objects > Triggers or /#admin/triggers). Review all existing trigger configurations for suspicious or unexpected entries.Affected if Any triggers are configured, especially those containing shell commands, script references, or unexpected parameters
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Inspect trigger execution logsReview Zammad logs for requests to the trigger API endpoints (typically /api/v1/triggers). Check application logs for command execution patterns.Affected if Recent logs show trigger creation or modification requests from admin users, particularly if the payloads contain encoded or unusual parameters
A system is affected if it runs any Zammad version below 4.1.1 AND has admin users with access to the triggers feature, as the vulnerability allows privilege escalation through trigger manipulation.
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. If immediate patching is not feasible, restrict admin account access and monitor for suspicious trigger configurations.
Zammad 4.1.1 or later
- 1. Back up your current Zammad installation and database before proceeding with any upgrade.
- 2. Check your current Zammad version to confirm it is affected (versions before 4.1.1).
- 3. Consult the official Zammad upgrade documentation for your specific installation method (package, source, Docker, etc.).
- 4. Upgrade to Zammad version 4.1.1 or later to remediate this vulnerability.
- 5. After upgrade, verify that triggers are functioning correctly and no unauthorized changes were made.
- 6. Review admin audit logs to confirm no unauthorized code execution occurred prior to the upgrade.
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation2.0 h
- Implementation3.0 h
- Testing2.0 h
- Review / QA1.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-42093 — 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-2021-42093 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
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- 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
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