CVE-2021-42094
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. Command Injection can occur via custom Packages.
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 · moderate confidenceZammad before 4.1.1 contains a command injection vulnerability in its custom Packages feature, allowing attackers to inject and execute arbitrary operating system commands through specially crafted packages.
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
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:N/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 Zammad installationLocate the Zammad installation directory or check running services. Common paths include /opt/zammad or /var/lib/zammad. On Linux, you can run 'ps aux | grep zammad' to find running processes.Affected if Zammad is not installed or no instance is found.
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Determine installed Zammad versionRun 'zammad --version' from the command line, or access the web UI, navigate to Admin > System > About, and locate the version number displayed there.Affected if Unable to retrieve version information.
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Compare version to affected rangeCheck if the installed version is less than 4.1.1. Compare the version number found in the previous step against 4.1.1.Affected if The installed version is lower than 4.1.1 (for example, 4.1.0, 4.0.x, or earlier).
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Verify custom Packages feature statusLog into the Zammad web interface as an administrator. Navigate to the admin settings and look for the Packages or Apps section (typically under Admin > Apps or Admin > Packages). Check whether any custom packages are installed or if the feature is accessible.Affected if The custom Packages feature is enabled and accessible to non-admin users, or custom packages are currently installed.
You are affected if your Zammad version is below 4.1.1 AND the custom Packages feature is enabled or has packages installed.
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 to Zammad version 4.1.1 or later. Until then, disable the custom Packages feature and avoid installing packages from untrusted sources.
Zammad 4.1.1
- Upgrade Zammad to version 4.1.1 or later to remediate the command injection vulnerability in custom Packages
- After upgrading, review any custom packages that have been installed for signs of compromise
- Verify the upgrade was successful by checking the Zammad version in the admin interface
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation4.0 h
- Implementation8.0 h
- Testing6.0 h
- Review / QA4.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-42094 — 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-2021-42094 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
- No spam, self-promotion, credentials, or personal data