CVE-2021-42091
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. SSRF can occur via GitHub or GitLab integration.
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 Server-Side Request Forgery (SSRF) vulnerability in its GitHub and GitLab integration features. An attacker could exploit this to make the Zammad server perform arbitrary requests to internal resources or unintended external services.
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
- None
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/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.
-
Determine your Zammad versionLog into the Zammad web interface as an administrator and navigate to the Admin area, or check the footer of any Zammad page for the version number. Alternatively, query the API endpoint /api/v1/health or check via command line if you have server access.Affected if The installed version is any version prior to 4.1.1 (for example, 4.1.0, 4.0.x, 3.x, etc.)
-
Check if GitHub integration is configuredIn the Zammad Admin interface, go to Settings > Integrations > GitHub. Look for any configured GitHub repositories or enabled GitHub integration settings.Affected if GitHub integration is enabled and has repositories configured, making the SSRF attack surface active
-
Check if GitLab integration is configuredIn the Zammad Admin interface, go to Settings > Integrations > GitLab. Look for any configured GitLab projects or enabled GitLab integration settings.Affected if GitLab integration is enabled and has projects configured, making the SSRF attack surface active
You are affected if your Zammad version is below 4.1.1 AND either the GitHub or GitLab integration feature is enabled with active configurations.
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 SSRF vulnerability. Additionally, restrict integration endpoints and monitor for anomalous requests originating from the Zammad server.
Zammad 4.1.1
- Backup your Zammad database and configuration files
- Review Zammad upgrade documentation for your deployment method
- Upgrade Zammad to version 4.1.1 or later
- Verify the GitHub and GitLab integrations are working correctly after upgrade
- Test that SSRF protections are in place by validating that the application cannot make arbitrary requests to internal resources
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
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,272.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-42091 — 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-2021-42091 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