CVE-2021-26559: CWE-284 Improper Access Control on Configurations Endpoint for the Stable API

Severity: medium (CVSS 6.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 2.8% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-02-17 · updated 2026-06-17
Weakness: CWE-284

Description

Improper Access Control on Configurations Endpoint for the Stable API of Apache Airflow allows users with Viewer or User role to get Airflow Configurations including sensitive information even when `[webserver] expose_config` is set to `False` in `airflow.cfg`. This allowed a privilege escalation attack. This issue affects Apache Airflow 2.0.0.

Affected products

Apache Airflow: 2.0.0

References

http://www.openwall.com/lists/oss-security/2021/02/17/1
https://lists.apache.org/thread.html/r3b3787700279ec361308cbefb7c2cce2acb26891a12ce864e4a13c8d%40%3Cusers.airflow.apache.org%3E
https://lists.apache.org/thread.html/rd142565996d7ee847b9c14b8a9921dcf80bc6bc160e3d9dca6dfc2f8%40%3Cannounce.apache.org%3E
http://www.openwall.com/lists/oss-security/2021/02/17/1
https://lists.apache.org/thread.html/r3b3787700279ec361308cbefb7c2cce2acb26891a12ce864e4a13c8d%40%3Cusers.airflow.apache.org%3E
https://lists.apache.org/thread.html/rd142565996d7ee847b9c14b8a9921dcf80bc6bc160e3d9dca6dfc2f8%40%3Cannounce.apache.org%3E

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