CVE-2026-41016 (GCVE-0-2026-41016)

Vulnerability from cvelistv5 – Published: 2026-04-30 09:09 – Updated: 2026-04-30 13:17
VLAI
Title
Apache Airflow Providers SMTP: No certificate validation on SMTP STARTTLS connections in SMTP provider
Summary
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.
Severity
5.9 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-30 13:16 UTC
CWE
  • CWE-295 - Improper Certificate Validation
Assigner
References
Impacted products
Credits
Francis Bergin (@francisbergin) Jarek Potiuk
Show details on NVD website
To clipboard 

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