CVE-2021-35936

Name: CVE-2021-35936
Creator: NVD / NIST
Published: 2021-08-16T08:15:11.53+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 5.3/10EPSS 4.02%

Last modified Jun 17, 2026

CVE-2021-35936 is a medium-severity vulnerability rated 5.3/10 on the CVSS scale. If remote logging is not used, the worker (in the case of CeleryExecutor) or the scheduler (in the case of LocalExecutor) runs a Flask logging server and is listening on a specific port and also binds on 0.0.0.0 by default. This logging server had no authentication and allows reading log files of DAG jobs. EPSS estimates a 4.02% chance of exploitation in the next 30 days.

Description

If remote logging is not used, the worker (in the case of CeleryExecutor) or the scheduler (in the case of LocalExecutor) runs a Flask logging server and is listening on a specific port and also binds on 0.0.0.0 by default. This logging server had no authentication and allows reading log files of DAG jobs. This issue affects Apache Airflow < 2.1.2.

Metrics

CVSS 3.1

5.3/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

EPSS Probability

4.02%

89.3th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Apache	Airflow	< 2.1.2

References

https://lists.apache.org/thread.html/r53d6bd7b0a66f92ddaf1313282f10fec802e71246606dd30c16536df%40%3Cusers.airflow.apache.org%3EMailing List, Vendor Advisory
https://lists.apache.org/thread.html/r53d6bd7b0a66f92ddaf1313282f10fec802e71246606dd30c16536df%40%3Cusers.airflow.apache.org%3EMailing List, Vendor Advisory

Timeline

Published: Aug 16, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-35936?

How severe is CVE-2021-35936?

CVE-2021-35936 has a CVSS score of 5.3/10 (MEDIUM severity). The EPSS model estimates a 4.02% probability of exploitation in the next 30 days.

How do I fix CVE-2021-35936?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-35936?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST