CVE-2021-35936

No Authentication on Logging Server

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.

Remediation

Workaround:

  • Use remote logging with GCS, S3, Elasticsearch etc. This is recommended for production environments. And do not publicly expose any other ports apart from Webserver port, Flower port etc.

Categories

5.3
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.24%
Vendor Advisory apache.org
Affected: Apache Software Foundation Apache Airflow
Published at:
Updated at:

References

Link Tags
https://lists.apache.org/thread.html/r53d6bd7b0a66f92ddaf1313282f10fec802e71246606dd30c16536df%40%3Cusers.airflow.apache.org%3E mailing list vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-35936?
CVE-2021-35936 has been scored as a medium severity vulnerability.
How to fix CVE-2021-35936?
As a workaround for remediating CVE-2021-35936: Use remote logging with GCS, S3, Elasticsearch etc. This is recommended for production environments. And do not publicly expose any other ports apart from Webserver port, Flower port etc.
Is CVE-2021-35936 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-35936 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-35936?
CVE-2021-35936 affects Apache Software Foundation Apache Airflow.
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