What is CVE-2020-13927?

CVE-2020-13927 is a critical-severity vulnerability in Apache Airflow, classified under Missing Authentication for Critical Function. CVSS score: 9.8/10. Published 2020-11-10.

How severe is CVE-2020-13927?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Is CVE-2020-13927 known to be exploited?

Yes. CVE-2020-13927 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2022-01-18), indicating it is being actively exploited. 9 public proof-of-concept repositories are indexed.

RCE in Apache Airflow

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

Vulnerability class: Broken Authentication

EPSS: 0.998 (100.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Apache Airflow
N/a Apache Airflow — versions Apache Airflow <1.10.11

Weakness classification (CWE)

CISA KEV (Known Exploited Vulnerabilities)

This CVE is on the CISA KEV catalog, added on 2022-01-18. CISA KEV inclusion means CISA has confirmed in-the-wild exploitation; US federal agencies are required to remediate within a published due date.

BOD 22-01 due date: 2022-07-18.

Required action: Apply updates per vendor instructions.

Public proof-of-concept exploits

References

security@apache.org (Mailing List, Vendor Advisory)
security@apache.org (Exploit, VDB Entry, Third Party Advisory)
security@apache.org (Exploit, VDB Entry, Third Party Advisory)
134c704f-9b21-4f2e-91b3-4a467353bcc0 (Third Party Advisory, US Government Resource)

Frequently asked questions

What is CVE-2020-13927?: CVE-2020-13927 is a critical-severity vulnerability in Apache Airflow, classified under Missing Authentication for Critical Function. CVSS score: 9.8/10. Published 2020-11-10.
How severe is CVE-2020-13927?: Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2020-13927 known to be exploited?: Yes. CVE-2020-13927 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2022-01-18), indicating it is being actively exploited. 9 public proof-of-concept repositories are indexed.