dbcve.org
Tableau ServerApplication · Tableau

CVE-2020-6939

CRITICAL · 9.8 CVSS v3.1 Published 2020-11-23
Fix available
A fix is available. Upgrade to after 2020.3.2 or later.
See remediation →
100/100
Remediation priority · Urgent
Remotely reachable No privileges Zero-click

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 · unedited
Tableau Server installations configured with Site-Specific SAML that allows the APIs to be used by unauthenticated users. If exploited, this could allow a malicious user to configure Site-Specific SAML settings and could lead to account takeover for users of that site. Tableau Server versions affected on both Windows and Linux are: 2018.2 through 2018.2.27, 2018.3 through 2018.3.24, 2019.1 through 2019.1.22, 2019.2 through 2019.2.18, 2019.3 through 2019.3.14, 2019.4 through 2019.4.13, 2020.1 through 2020.1.10, 2020.2 through 2020.2.7, and 2020.3 through 2020.3.2.

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 confidence

Tableau Server with Site-Specific SAML configuration contains an authentication bypass vulnerability where APIs can be accessed without authentication. An unauthenticated attacker can manipulate SAML settings for a specific site, potentially leading to full account takeover of users within that site.

MitigationUpgrade Tableau Server to the latest patched version (beyond 2020.3.2) or apply the relevant hotfix. Alternatively, review and harden SAML configuration settings to ensure all API endpoints require proper authentication.

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
Tableau ServerApplication
Affected:>= 2018.2, <= 2018.2.27>= 2018.3, <= 2018.3.24>= 2019.1, <= 2019.1.22>= 2019.2, <= 2019.2.18>= 2019.3, <= 2019.3.14>= 2019.4, <= 2019.4.13>= 2020.1, <= 2020.1.10>= 2020.2, <= 2020.2.7>= 2020.3, <= 2020.3.2

CVSS 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 checks

Work through these to decide whether this CVE applies to you.

  1. Identify installed Tableau Server version
    Access the Tableau Server Administration area or use the `tsm version` command line tool to retrieve the exact version number installed.
    Affected if The installed version falls within any of these ranges: 2018.2 to 2018.2.27, 2018.3 to 2018.3.24, 2019.1 to 2019.1.22, 2019.2 to 2019.2.18, 2019.3 to 2019.3.14, 2019.4 to 2019.4.13, 2020.1 to 2020.1.10, 2020.2 to 2020.2.7, or 2020.3 to 2020.3.2.
  2. Verify SAML authentication is enabled
    Navigate to Tableau Server Settings > Authentication and confirm if SAML is selected as the authentication method for any site.
    Affected if SAML authentication is enabled on the Tableau Server.
  3. Confirm site-specific SAML configuration
    Check whether SAML is configured at the individual site level rather than globally for the entire server. This can be verified in the site settings under Authentication for each site.
    Affected if SAML is configured for specific sites (site-specific SAML) rather than globally.
  4. Test API endpoint accessibility
    Attempt to access Tableau Server REST API endpoints without providing valid authentication credentials. Specifically test endpoints related to site settings and SAML configuration.
    Affected if API endpoints can be accessed or manipulated without authentication, particularly those affecting SAML settings for a site.

The environment is affected if the installed Tableau Server version is within the affected ranges AND site-specific SAML authentication is enabled, allowing unauthenticated API access to SAML configuration endpoints.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

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 · scoped
Upgrade available Upgrade to a release after 2020.3.2
Interim mitigation

Upgrade Tableau Server to the latest patched version (beyond 2020.3.2) or apply the relevant hotfix. Alternatively, review and harden SAML configuration settings to ensure all API endpoints require proper authentication.

Recommended fix High confidence

Tableau Server 2018.2.28+, 2018.3.25+, 2019.1.23+, 2019.2.19+, 2019.3.15+, 2019.4.14+, 2020.1.11+, 2020.2.8+, or 2020.3.3+ (latest supported release recommended)

  1. 1. Identify the currently installed Tableau Server version by checking the server or using the Tableau Server CLI: tsm version
  2. 2. Determine which upgrade path applies based on your current version (2018.2.x -> 2018.2.28+, 2018.3.x -> 2018.3.25+, 2019.1.x -> 2019.1.23+, 2019.2.x -> 2019.2.19+, 2019.3.x -> 2019.3.15+, 2019.4.x -> 2019.4.14+, 2020.1.x -> 2020.1.11+, 2020.2.x -> 2020.2.8+, 2020.3.x -> 2020.3.3+)
  3. 3. Review Tableau Server upgrade documentation for your specific version jump to ensure compatibility
  4. 4. Perform a full backup of the Tableau Server repository, configuration, and topology before upgrading
  5. 5. Run the upgrade installer for the chosen fixed version on all nodes in the cluster
  6. 6. Verify the SAML configuration is intact post-upgrade and test authentication flows
  7. 7. Confirm the vulnerability is resolved by verifying Site-Specific SAML API endpoints now require authentication
Caveat Upgrading across major version branches (e.g., 2018.x to 2020.x) may require configuration changes and compatibility review; refer to Tableau upgrade documentation for breaking changes between versions

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Tableau Server Scoped from the published advisory
  • Consultation3.0 h
  • Implementation6.0 h
  • Testing4.0 h
  • Review / QA2.0 h
15.0 hours of engineering $2,640
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $4,224.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2020-6939 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2020-6939 in production — separate from our analysis above.

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.

What this is

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.

What belongs here
  • 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