CVE-2020-26030
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 3.4.1. There is an authentication bypass in the SSO endpoint via a crafted header, when SSO is not configured. An attacker can create a valid and authenticated session that can be used to perform any actions in the name of other users.
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 3.4.1 contains an authentication bypass vulnerability in the SSO endpoint. When SSO is not configured, an attacker can send a crafted header to the SSO endpoint to create a valid, authenticated session. This session can then be used to impersonate any user in the system and perform actions on their behalf.
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>= 1.0.0, < 3.4.1CVSS 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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Determine installed Zammad versionLocate the Zammad version number in your installation (typically visible in the web UI footer, admin panel, or via command line tools such as 'zammad --version' or checking package metadata)Affected if The installed version is 1.0.0 or higher but lower than 3.4.1
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Verify SSO configuration statusAccess the Zammad admin panel and navigate to the SSO/SAML settings area, or inspect the configuration files for SSO parametersAffected if SSO is not enabled or not properly configured in the environment
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Confirm SSO endpoint accessibilityCheck if the SSO endpoint (/auth/sso or similar) is exposed and reachable without authentication requirementsAffected if The SSO endpoint accepts requests without requiring valid SSO configuration to be in place
Your environment is affected if Zammad version is below 3.4.1 AND SSO is not properly configured, allowing unauthenticated access to the SSO endpoint.
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 · scoped3.4.1
Upgrade Zammad to version 3.4.1 or later to patch this vulnerability. Additionally, review SSO configuration and ensure proper authentication controls are in place.
Zammad 3.4.1 or later (preferably latest stable 3.x release)
- 1. Back up the Zammad database and application data before proceeding with any upgrade
- 2. Check the current Zammad version running in your environment
- 3. Review the Zammad 3.4.x release notes for any pre-upgrade requirements or migration steps
- 4. Upgrade Zammad to version 3.4.1 or later (recommended: latest stable 3.x release)
- 5. After upgrade, verify the SSO endpoint is properly configured if SSO is being used, or ensure it remains disabled if not needed
- 6. Test authentication flows to confirm the vulnerability is resolved
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation2.0 h
- Implementation4.0 h
- Testing3.0 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 $2,800.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2020-26030 — 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-2020-26030 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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- Version or environment caveats, and links to real fixes
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