CVE-2021-38540 in the critical feed json
Apache Airflow: Variable Import endpoint missed authentication check
published 2021-09-09 5 y ago modified 2026-09-08 2 mo ago also BIT-airflow-2021-38540 , EUVD-2021-0016 , GHSA-h88f-r7cw-8fv3 , PYSEC-2021-326
- cvss
- 9.8
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 80.9%
- EPSS 80.9% chance of exploitation in 30 days, percentile 99.6%
- public exploits
- 0
- none known, plus a Nuclei check
Summary
The variable import endpoint was not protected by authentication in Airflow >=2.0.0, <2.1.3. This allowed unauthenticated users to hit that endpoint to add/modify Airflow variables used in DAGs, potentially resulting in a denial of service, information disclosure or remote code execution. This issue affects Apache Airflow >=2.0.0, <2.1.3.
Patch / fix
- pypi apache-airflow 2.1.3
- bitnami airflow 2.1.3
- Apache Software Foundation Apache Airflow 2.1.3
Exploit prediction
80.94% chance of exploitation in the next 30 days, higher than 99.6% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- Nuclei template Apache Airflow - Unauthenticated Variable Import nuclei detection template
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| GitHub | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVD | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVD | 2.0 | 7.5 | AV:N/AC:L/Au:N/C:P/I:P/A:P |
| OSV | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| pypi | apache-airflow | >=2.0.0, <2.1.3 |
2.1.3 |
| bitnami | airflow | >=2.0.0, <2.1.3 |
2.1.3 |
Affected products
- Apache Software Foundation Apache Airflow
Classification
References
-
github.com
/apache/airflow/commit/bcec1df703cd4a01520a90c3f801cca6f97d9bfd
web
-
lists.apache.org
/thread.html/rb34c3dd1a815456355217eef34060789f771b6f77c3a3dec77de2064%40%3Cusers.airflow.apache.org%3E
web, mailing-list, vendor-advisory, advisory
-
lists.apache.org
/thread.html/rac2ed9118f64733e47b4f1e82ddc8c8020774698f13328ca742b03a2%40%3Cannounce.apache.org%3E
mailing-list, web
-
nvd.nist.gov
/vuln/detail/CVE-2021-38540
advisory, web
-
github.com
/advisories/GHSA-h88f-r7cw-8fv3
advisory
-
github.com
/apache/airflow
package
-
github.com
/pypa/advisory-database/tree/main/vulns/apache-airflow/PYSEC-2021-326.yaml
web
-
lists.apache.org
/thread.html/rac2ed9118f64733e47b4f1e82ddc8c8020774698f13328ca742b03a2@%3Cannounce.apache.org%3E
web
Sources
- CVE List CVE-2021-38540
- GitHub Advisory GHSA-h88f-r7cw-8fv3
- NVD CVE-2021-38540
- OSV BIT-airflow-2021-38540
- OSV PYSEC-2021-326
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