By Default, Insecure: Apache Airflow Disables SSH Host Key Verification

OX Security researchers found that Apache Airflow's SSH and SFTP provider packages ship with host key verification turned off by default, exposing pipeline connections to man-in-the-middle attacks. Two High-severity flaws (CVSS 8.1) were assigned: CVE-2026-94134 for the synchronous SSH/SFTP hooks, which fall back to paramiko's AutoAddPolicy and silently accept any server key, and CVE-2026-94135 for the asynchronous SFTP path, which passes known_hosts=None to asyncssh. Both affect apache-airflow-providers-ssh and apache-airflow-providers-sftp through version 6.0.1, and are fixed in version 7.0.0 of each package. Since the insecure behavior is the out-of-the-box default rather than something users must deliberately enable, an attacker able to intercept traffic between an Airflow worker and a remote server can hijack the session to steal credentials, tamper with transferred files, or inject command output — with the only warning appearing in task logs after the connection is already established. Operators are advised to upgrade both providers to 7.0.0 or higher and, in the meantime, explicitly set no_host_key_check=false with a valid host_key on every existing SSH/SFTP connection.