How severe is CVE-2020-13927?

CVE-2020-13927 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2020-13927 being actively exploited?

Yes. CVE-2020-13927 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2022-01-18, which means active exploitation has been confirmed. It should be prioritised for remediation.

What products are affected by CVE-2020-13927?

CVE-2020-13927 affects Apache Airflow. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-13927?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.

Does CVE-2020-13927 have an EU (EUVD) identifier?

Yes. CVE-2020-13927 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2020-0037. It is also flagged as exploited in the EUVD (since 2022-01-18).

When was CVE-2020-13927 published?

CVE-2020-13927 was published on 2020-11-10 and last updated on 2026-06-17.

CVE-2020-13927

CVE-2020-13927 is a critical-severity vulnerability in Apache Airflow with a CVSS 3.x base score of 9.8. It is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, confirming it has been exploited in the wild (added 2022-01-18). The underlying weakness is classified as CWE-306.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 100% (100th percentile)
Actively exploited: Yes — listed in CISA KEV (added 2022-01-18)
EU (EUVD) id: EUVD-2020-0037
EU exploitation: Flagged exploited in the ENISA EU Vulnerability Database (since 2022-01-18)
Weakness: CWE-306
Affected product: Apache Airflow
Published: 2020-11-10
Last modified: 2026-06-17

Description

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

Frequently asked questions

What is CVE-2020-13927?: 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
How severe is CVE-2020-13927?: CVE-2020-13927 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2020-13927 being actively exploited?: Yes. CVE-2020-13927 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2022-01-18, which means active exploitation has been confirmed. It should be prioritised for remediation.
What products are affected by CVE-2020-13927?: CVE-2020-13927 affects Apache Airflow. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-13927?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.
Does CVE-2020-13927 have an EU (EUVD) identifier?: Yes. CVE-2020-13927 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2020-0037. It is also flagged as exploited in the EUVD (since 2022-01-18).
When was CVE-2020-13927 published?: CVE-2020-13927 was published on 2020-11-10 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:apache:airflow:*:*:*:*:*:*:*:*

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Threat intelligence

Threat-intel indicators referencing this CVE:

8.211.195.173 (ipv4-addr)
8.212.165.164 (ipv4-addr)