CVE-2023-42780 in Airflow
Summary
by MITRE • 10/25/2023
Apache Airflow, versions prior to 2.7.2, contains a security vulnerability that allows authenticated users of Airflow to list warnings for all DAGs, even if the user had no permission to see those DAGs. It would reveal the dag_ids and the stack-traces of import errors for those DAGs with import errors. Users of Apache Airflow are advised to upgrade to version 2.7.2 or newer to mitigate the risk associated with this vulnerability.
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Analysis
by VulDB Data Team • 11/02/2023
Apache Airflow versions prior to 2.7.2 contain a critical authorization bypass vulnerability that fundamentally undermines the security model of the platform. This vulnerability resides in the warning listing functionality where authenticated users can enumerate warnings for all DAGs within the system regardless of their actual permissions or access rights to those specific DAGs. The flaw represents a significant information disclosure issue that directly violates the principle of least privilege and proper access control enforcement. The vulnerability affects the core authorization mechanisms that should prevent users from accessing sensitive information about DAGs they do not have permissions to view, creating a scenario where unauthorized information exposure occurs at the application level.
The technical implementation of this vulnerability stems from insufficient authorization checks within the warning listing endpoints. When users request to view warnings for DAGs, the system fails to properly validate whether the requesting user has legitimate access rights to view the specific DAGs in question. This authorization gap allows users to submit requests that return comprehensive information including dag_ids and detailed stack-traces of import errors for DAGs they should not be able to access. The vulnerability is particularly concerning because it exposes not only the existence of certain DAGs but also provides technical details about why those DAGs might be failing, potentially revealing implementation details, file paths, and error patterns that could be exploited by malicious actors.
The operational impact of this vulnerability extends beyond simple information disclosure to create potential attack vectors for more sophisticated exploitation attempts. Attackers who gain access to Airflow through legitimate means can use this vulnerability to map the entire DAG landscape, identify potential entry points, and understand the structure of the workflow system. The stack-trace information reveals internal implementation details that could be leveraged to craft more targeted attacks against the system or to identify additional vulnerabilities. This vulnerability directly impacts the confidentiality aspect of the CIA triad and can enable further reconnaissance activities that would otherwise be blocked by proper access controls. The exposure of DAG identifiers also provides attackers with knowledge of the system's operational structure, potentially allowing them to target specific workflows or identify sensitive data processing pipelines.
Organizations using affected Apache Airflow versions should immediately implement the recommended upgrade to version 2.7.2 or later to remediate this vulnerability. The fix addresses the authorization bypass by implementing proper access control checks before returning warning information for DAGs. Security teams should also consider implementing additional monitoring for unusual warning listing activities and establish proper audit trails for DAG access patterns. This vulnerability aligns with CWE-284 which addresses improper access control, and could potentially be leveraged in conjunction with other techniques to achieve privilege escalation or information gathering as outlined in ATT&CK matrix domain T1566 for credential access and T1083 for file and directory discovery. Organizations should also review their overall Airflow security posture and ensure that proper user role definitions and access control policies are implemented to prevent similar issues from occurring in other parts of the system.