CVE-2026-41016Medium· 5.9▾ Sunlitapache-airflow-providers-smtp: No certificate validation on SMTP STARTTLS connections in SMTP provider
▾ Sunlit zone — Low / medium · no exploitation signal
impact 32.5 · likelihood 0.1 · exploitation 0
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Exploit-prediction probability, daily snapshots since Sep 12.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via OSV
Last analysed / modified upstream
0.3%
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.
apache-airflow-providers-smtp >= 2.0.0, < 3.0.0Upgrade to a patched release:
apache-airflow-providers-smtp 3.0.0Connected by shared product, vendor, weakness, or advisory.