CVE-2026-41016
MEDIUMApache Airflow Providers SMTP: No certificate validation on SMTP STARTTLS connections in SMTP provider
Title source: cnaDescription
Apache Airflow's SMTP provider `SmtpHook` called Python's `smtplib.SMTP.starttls()` without an SSL context, so no certificate validation was performed on the TLS upgrade. A man-in-the-middle between the Airflow worker and the SMTP server could present a self-signed certificate, complete the STARTTLS upgrade, and capture the SMTP credentials sent during the subsequent `login()` call. Users are advised to upgrade to the `apache-airflow-providers-smtp` version that contains the fix.
References (2)
Core 2
Core References
Patch patch
https://github.com/apache/airflow/pull/65346
Vendor Advisory vendor-advisory
https://lists.apache.org/thread/gb202qy5r31bgdd3d51d7s5o1jh40kc4
Scores
CVSS v3
5.9
EPSS
0.0023
EPSS Percentile
13.1%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
no
Technical Impact
partial
Details
CWE
CWE-295
Status
published
Products (3)
apache/airflow
2.0.0 - 3.0.0
Apache Software Foundation/Apache Airflow Providers SMTP
2.0.0 - 3.0.0
pypi/apache-airflow-providers-smtp
2.0.0 - 3.0.0PyPI
Published
Apr 30, 2026
Tracked Since
Apr 30, 2026