Apache Airflow SSH provider: Missing host key verification by default
Summary
The Apache Airflow SSH and SFTP providers do not verify SSH host keys by default unless host_key is configured or no_host_key_check is explicitly set to false, so any server key is accepted. An attacker in a man-in-the-middle position between the Airflow worker and the SSH or SFTP server can impersonate the server. This can expose credentials and data sent by Airflow tasks.
Affected
- apache-airflow-providers-ssh before 7.0.0
- apache-airflow-providers-sftp before 7.0.0 (the deferrable SFTP code paths are covered separately by CVE-2026-94135)
Fixed in
- apache-airflow-providers-ssh 7.0.0 or later
- apache-airflow-providers-sftp 7.0.0 or later (fixes CVE-2026-94134 and CVE-2026-94135)
Workaround
Unknown. No vendor-documented workaround for older versions was found.
- Explicitly configuring host_key on each SSH and SFTP connection avoids the default path. This is inferred from the advisory, not vendor guidance.
Exploitation
- CISA SSVC data in the official CVE record: exploitation none, automatable yes, technical impact partial.
- No evidence of exploitation in the wild was found.
- An unverified aggregator entry lists a public exploit. It has not been verified.
Our recommendation
- Inventory Airflow installations and check the installed apache-airflow-providers-ssh and apache-airflow-providers-sftp versions.
- Upgrade both packages to 7.0.0 or later.
- Until the upgrade is done, set host_key explicitly on SSH and SFTP connections and limit worker traffic to trusted network paths.
- Review which credentials are sent over networks that are not fully trusted.
Public exploits
Links to third-party sites, not checked by us – exploit code can contain malware. Only use it in isolated test environments.
- Proof of concept on GitHub (1 repositories)
MosesOX/POC-CVE-2026-94134
Research sources
- Apache mailing list advisory lists.apache.org
- Apache Airflow pull request #73419 (fix) github.com
- OX Security analysis www.ox.security
- OpenCVE record CVE-2026-94134 app.opencve.io
- Vulners NVD record CVE-2026-94134 vulners.com
Researched and written up in English and German by an AI (Claude by Anthropic) based on NVD, CISA, EPSS and the sources listed. The vendor information is authoritative. Researched on 31 Oct 2026, 06:26.
Original description (NVD)
The Apache Airflow SSH provider hook disables SSH host-key verification by default: unless `host_key` is configured or `no_host_key_check` is explicitly set to false, it accepts any server key. This affects SSH and SFTP connections that rely on the default. An attacker in a machine-in-the-middle position between the worker and the SSH or SFTP server can impersonate the server and capture the credentials or data a task sends. Users of apache-airflow-providers-ssh and apache-airflow-providers-sftp are recommended to upgrade to apache-airflow-providers-ssh 7.0.0 and apache-airflow-providers-sftp 7.0.0 or later. The deferrable SFTP code paths had the same default and are covered separately by CVE-2026-94135; apache-airflow-providers-sftp 7.0.0 fixes both.
Sources
The tracker combines official, freely usable data sources – updated continuously:
- NVD (NIST) – CVEs, rating (CVSS), affected products
- CISA KEV – vulnerabilities confirmed by CISA as actively exploited
- CISA Vulnrichment – CISA assessment (SSVC) in the official CVE record
- FIRST EPSS – probability of exploitation
- Microsoft MSRC – Patch Tuesday: vulnerabilities, severity, updates
- PoC-in-GitHub – public proof-of-concept repositories
- Metasploit (Rapid7) – modules of the Metasploit Framework
- Exploit-DB (OffSec) – archive of public exploits (links only)
- Patch days: official vendor pages (linked per vendor) (Vendor patch days)
This product uses data from the NVD API but is not endorsed or certified by the NVD. EPSS data © FIRST.org.
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