CVE-2021-42086
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 Agent account can modify account data, and gain admin access, via a crafted request.
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 confidenceA privilege escalation vulnerability in Zammad before version 4.1.1 allows authenticated Agent-level users to modify their own account data through a crafted HTTP request, enabling them to gain unauthorized administrative access to the system.
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
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:L/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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Check installed Zammad versionRun `zammad --version` or check the package manager for the installed Zammad version. On the web interface, this may also be visible in the system information or admin dashboard.Affected if The installed version is any version before 4.1.1 (e.g., 4.0.0, 3.x, etc.)
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Verify Agent user accounts existAccess the Zammad admin panel, navigate to Users or Members section, and identify accounts with Agent role. The vulnerability affects environments with at least one Agent-level user account.Affected if There are Agent-level users defined in the system and the Zammad version is below 4.1.1
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Review admin role assignmentsCheck the Users admin panel to identify which accounts have the Admin role. Look for any accounts with Admin role that should not have elevated privileges based on your organizational records.Affected if Any user has been granted Admin role unexpectedly or there are admin users you did not create
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Audit account modification logsReview Zammad's audit logs (typically found in Admin > Logs > Audit Log) for entries showing Agent users modifying their own user objects, particularly role or permission attributes.Affected if There are log entries showing Agent users modified their own account roles or permissions, or modified the admin attribute on their user record
Your environment is affected if Zammad version is below 4.1.1 AND there are Agent-level users present in the system who could potentially exploit the account data modification to escalate to Admin privileges.
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 remediate the authorization bypass vulnerability.
4.1.1
- Backup your current Zammad database and configuration
- Stop the Zammad service
- Upgrade Zammad to version 4.1.1 or later using your installation method (package manager, source, or container)
- Restart the Zammad service
- Verify the upgrade was successful by checking the Zammad version and logging in
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation2.0 h
- Implementation4.0 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 $2,560.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-42086 — 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-2021-42086 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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