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Actively exploited in the wild. This CVE is on the CISA Known Exploited Vulnerabilities list — treat remediation as urgent. Federal remediation due by 18 Jul 2022.
AirflowApplication · Apache

CVE-2020-13927

CRITICAL · 9.8 CVSS v3.1 Published 2020-11-10
Fix available
A fix is available. Upgrade to 1.10.11 or later.
See remediation →
100/100
Remediation priority · Urgent
In the wild High EPSS Public exploit 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
The previous default setting for Airflow's Experimental API was to allow all API requests without authentication, but this poses security risks to users who miss this fact. From Airflow 1.10.11 the default has been changed to deny all requests by default and is documented at https://airflow.apache.org/docs/1.10.11/security.html#api-authentication. Note this change fixes it for new installs but existing users need to change their config to default `[api]auth_backend = airflow.api.auth.backend.deny_all` as mentioned in the Updating Guide: https://github.com/apache/airflow/blob/1.10.11/UPDATING.md#experimental-api-will-deny-all-request-by-default

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

The Apache Airflow Experimental API had an insecure default configuration where all API requests were allowed without authentication. This created an authentication bypass vulnerability allowing unauthenticated attackers to access sensitive Airflow data, execute DAGs, and potentially pivot to other systems. Version 1.10.11 changed the default to deny all requests, requiring explicit authentication configuration.

MitigationExisting Airflow deployments must update their configuration to set `[api]auth_backend = airflow.api.auth.backend.deny_all` or configure an appropriate authentication backend (like kerberos, jwt, or basic auth) before restarting the Airflow 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
AirflowApplication
Affected:< 1.10.11

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. Check installed Airflow version
    Run `airflow version` or `pip show apache-airflow` to see the installed version number
    Affected if The version is less than 1.10.11 (e.g., 1.10.10, 1.10.9, 1.10.8, etc.)
  2. Locate the Airflow configuration file
    Find airflow.cfg typically in $AIRFLOW_HOME directory, or check for environment variable AIRFLOW_CONFIG pointing to the config file
    Affected if You cannot locate the configuration file to verify API settings
  3. Verify API authentication backend setting
    Open airflow.cfg and look for the `[api]` section. Check the `auth_backend` setting under that section
    Affected if The `auth_backend` is not set (commented out or missing) OR is set to a permissive backend like `airflow.api.auth.backend.basic_auth` without proper authentication configured, AND the version is below 1.10.11
  4. Check if Experimental API is enabled
    In airflow.cfg, look for `enable_experimental_api` under the `[api]` section or check if the API is accessible on port 8080/airflow/api/experimental/
    Affected if `enable_experimental_api` is set to True AND the version is below 1.10.11 with no auth_backend configured

You are affected if running Airflow version below 1.10.11 with the Experimental API enabled and no explicit auth_backend configured in airflow.cfg - this means unauthenticated API access is possible.

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 1.10.11 or later
Fixed in 1.10.11
Interim mitigation

Existing Airflow deployments must update their configuration to set `[api]auth_backend = airflow.api.auth.backend.deny_all` or configure an appropriate authentication backend (like kerberos, jwt, or basic auth) before restarting the Airflow services.

Recommended fix High confidence

1.10.11

  1. Upgrade Apache Airflow to version 1.10.11 or later
  2. For existing installations, verify or set `[api]auth_backend = airflow.api.auth.backend.deny_all` in the airflow.cfg configuration file
  3. Restart all Airflow services (webserver, scheduler, worker) to apply the configuration changes
  4. If API access is needed, configure an appropriate auth backend such as `airflow.api.auth.backend.basic_auth` or `airflow.api.auth.backend.kerberos_auth`
Caveat The Experimental API now denies all requests by default; existing API consumers will require authentication or explicit backend configuration

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

Fix this in Airflow Exploited in the wild — priority engagement
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  • Review / QA1.0 h
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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

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Peer-ranked notes from engineers who’ve handled CVE-2020-13927 in production — separate from our analysis above.

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What belongs here
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  • Version or environment caveats, and links to real fixes
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